Answered questions
Nutrition & prevention
291 answered questions · 2,004 studies
All topicsNutrition & preventionMuscles & movementHeart & vesselsBrain & memoryCancerInterventionsSleepAging clocksCells & DNAGut & microbiomeSkinHormonesImmune systemBonesMetabolism
Do goji berries help against ageing?
Goji has shown interesting properties in experiments with cells and in animal studies. In people, its effect on ageing has…
Preliminary evidence
Why do Japanese people live so long?
The Japanese dietary pattern, rich in vegetables and fish and low in fat, is clearly associated with a longer and healthier…
Is brown rice healthier than white rice?
Brown rice is more nutritious than white rice and produces a lower blood sugar spike, but only in its ordinary form, not the…
Yes · Moderate evidence
What is the Korean slow-ageing diet and does it work?
A Korean eating pattern built on wholegrains, legumes, vegetables, fruit and fish is linked in several studies to fewer…
Moderate evidence
Does the PhenoAge test measure your biological age with standard blood values?
Standard blood test results can provide an estimate of your biological age through PhenoAge, and that estimate predicts health…
What do psyllium and flaxseed do for your blood sugar?
Taking psyllium before a meal demonstrably lowers the blood sugar peak in people with type 2 diabetes, and with longer use…
Are emulsifiers and sweeteners harmful?
There are serious indications that widely used emulsifiers and artificial sweeteners can disrupt the gut microbiome and may be…
Preliminary evidence
Is intermittent fasting suitable for women over forty?
Intermittent fasting is a viable approach for women over forty, including after menopause, for weight management and improved…
Yes · Moderate evidence
Which form of intermittent fasting works best?
Alternate-day fasting has the strongest short-term evidence for weight loss, but the advantage over simply eating less is…
Moderate evidence
Which form of fasting works best against belly fat?
Alternate-day fasting and the 5:2 pattern show the strongest evidence for loss of belly fat, but the studies are short-term or…
Moderate evidence
Which cancers does alcohol play a role in?
Alcohol increases the risk of several types of cancer, most strongly for mouth, throat, oesophageal and liver cancer. Even at…
What does eating an avocado every day do for your health?
Eating an avocado every day probably has beneficial effects on your cholesterol, especially when you use it to replace other,…
Which antioxidants have been proven to be beneficial?
Vitamin E has the best evidence base, particularly for asthma in children. For most other applications the indications are…
Preliminary evidence
Why does magnesium work for some people but not others?
Whether magnesium works for you depends strongly on which form you take and how high your dose is. Preferably choose an…
Does the timing of your meals affect how long you live?
The timing of your meals is associated with biological ageing and risk of death, but cause and effect have not been proven.…
Yes · Moderate evidence
Does eating a low-protein diet extend your life, or does that only apply to mice?
Eating less animal protein appears beneficial in middle age, but after the age of 65 getting enough protein is actually…
Moderate evidence
Does the 16:8 schedule work better than other forms of intermittent fasting?
16:8 works better than shorter fasting windows in the short term, but over the long term it is not demonstrably better than…
Moderate evidence
Can intermittent fasting cause constipation?
Intermittent fasting can temporarily cause constipation, but in people who already suffer from constipation as a bowel…
Preliminary evidence
Does intermittent fasting lower your cholesterol?
Intermittent fasting probably lowers total cholesterol and LDL modestly, but its effect on 'good' HDL cholesterol is unclear…
Yes · Moderate evidence
How much magnesium glycinate can you safely take per day?
In Europe the limit is 250 mg of elemental magnesium per day from supplements (350 mg in the United States), although more…
Preliminary evidence
Do you live longer from playing tennis or squash?
For tennis there are indications of a substantial gain in life expectancy, but for squash the evidence is entirely absent. If…
Preliminary evidence
Is 75 minutes of exercise per week already enough?
75 minutes of vigorous exercise per week already delivers close to the maximum benefit for your lifespan. On top of that, make…
Yes · Strong evidence
What your resting heart rate says about your life expectancy
A higher resting heart rate is clearly and consistently linked to a higher risk of premature death, even after taking other…
How many extra years of life does regular walking provide?
Regular walking is associated with two to six extra years of life, with the greatest gain for people who currently barely…
Moderate evidence
How much longer do you live from fifteen minutes of exercise a day?
Just fifteen minutes of moderate exercise a day is associated with an average of 3 years of longer life expectancy. Doing more…
Does lutein from avocado protect your eyesight?
Avocado raises your lutein intake and appears to improve macular pigment density, but the direct evidence for this is limited…
Moderate evidence
Can you reduce the risk of Parkinson's disease?
Regular physical activity is the best lifestyle choice for reducing your risk of Parkinson's disease: more exercise is…
Yes · Moderate evidence
Does avocado help you absorb vitamins?
Avocado measurably helps with the absorption of fat-soluble vitamins and carotenoids from other vegetables. A few slices on…
Yes · Moderate evidence
Does avocado help lower your blood sugar spike after a meal?
If you eat half or a whole avocado in place of carbohydrates, there is preliminary evidence that your post-meal blood sugar…
Moderate evidence
Does eating an avocado every day improve the diversity of your gut microbiome?
Eating an avocado every day likely increases the diversity of your gut bacteria, although the evidence comes primarily from…
Yes · Moderate evidence
Do you live longer if you eat more salt?
Eating more salt does not lead to a longer life. At the individual level, it demonstrably increases the risk of cardiovascular…
No · Strong evidence
Does extra salt help with fatigue during fasting?
Baking soda (sodium bicarbonate) reduced fatigue in trained men who had fasted and then exercised, but this was found in only…
Preliminary evidence
Do phyto-oestrogens in soy reduce menopausal symptoms?
Soy isoflavones may reduce hot flushes somewhat, but the effect is modest and the studies contradict each other enough that…
Moderate evidence
Does green tea enhance the effect of exercise?
Green tea adds a small but measurable extra effect on top of exercise in terms of weight loss and inflammatory markers. For…
Yes · Moderate evidence
Does a Mediterranean diet help reduce belly fat?
A Mediterranean diet demonstrably helps reduce belly fat, and a polyphenol-rich variant with green tea and walnuts appears to…
Yes · Moderate evidence
Does eating low-carb make a difference for belly fat?
Eating low-carb probably helps with belly fat, but the effect depends strongly on how strictly you follow it and whether you…
Preliminary evidence
How much lithium do you need each day?
There is no official daily recommendation for lithium; scientists cite 1 mg per day as a cautious guideline, but evidence for…
Preliminary evidence
What does an omega-3 deficiency do to your brain and mental resilience?
An omega-3 deficiency demonstrably harms the brain, especially during early development and in depression. If you have…
Does omega-3 prevent postnatal depression?
Omega-3 supplements have not been shown to prevent postnatal depression, and as a treatment the evidence is still too…
No · Moderate evidence
What is the optimal vitamin D level?
For bone health, 50 nmol/l is the most widely accepted target level, achievable with 800 IU of vitamin D per day. Whether a…
Moderate evidence
Which skincare actually works after forty?
A number of skincare ingredients have a proven effect after forty: tretinoin (on prescription) is the best-supported option,…
Moderate evidence
Which supplements genuinely support your immune system?
Some supplements genuinely support your immune system, but the effect is greatest when you have a deficiency: so first check…
Moderate evidence
How does nutrition strengthen your immune system?
Nutrition has a clear influence on the immune system: deficiencies weaken your defences, and correcting a demonstrable…
Moderate evidence
How can you speed up or improve your metabolism?
You can influence your metabolism, but the effects are more modest than popular claims suggest. Most of the gain lies in more…
Moderate evidence
Is eating 800 grams of fruit and vegetables a day healthier than the standard guideline?
More than 400 grams a day helps, but whether 800 grams is clearly healthier than 400 grams depends on your goal: for heart and…
Moderate evidence
Does drinking water help with weight loss?
Drinking water probably helps with weight loss, especially when done before meals or used to replace sugary drinks. The effect…
Yes · Moderate evidence
Which fermented foods are the healthiest?
Yoghurt has the strongest support: regular consumption is linked to a lower risk of diabetes and heart and vascular disease.…
Moderate evidence
How do you use peptides for the best results?
For most peptide supplements that you simply swallow, absorption into the bloodstream is so low that little benefit can be…
Preliminary evidence
Does a daily multivitamin protect memory in older age?
A daily multivitamin appears to offer modest memory protection in older people who are at risk of nutritional shortfalls or…
Moderate evidence
Do tanning beds give you vitamin D?
A sunbed can raise your vitamin D level, but only if the light also contains UV-B, and most commercial beds emit very little…
Moderate evidence
Do you live longer by eating less protein, or more?
The ideal protein level differs by stage of life: in middle age less appears to be better, while after the age of 65 getting…
Moderate evidence
Can you drink coffee with milk while fasting?
Milk in coffee breaks your fast: it stimulates insulin release and counts as food intake. If you want to keep your fasting…
No · Preliminary evidence
What does 12:12 fasting deliver compared with 16:8?
16:8 fasting demonstrably produces more weight and fat loss in healthy adults than 12:12, which showed no measurable effect…
Is intermittent fasting safe during pregnancy?
For healthy pregnant women, fasting does not appear to increase major risks such as preterm birth or low birth weight, but…
Moderate evidence
What is the difference between magnesium bisglycinate and magnesium glycinate?
Magnesium bisglycinate and magnesium glycinate are two names for the same supplement. Whether it is absorbed better than…
Does eating spicy food help you live longer?
Eating spicy food regularly is linked to a lower chance of dying early, but whether it is the cause is not yet known. With…
Moderate evidence
Is intermittent fasting safe if you have type 2 diabetes?
Intermittent fasting can be safe in type 2 diabetes, but only if you do this in consultation with your doctor, because your…
Yes · Moderate evidence
What is spermidine and where is it found?
Spermidine is a molecule that occurs naturally in your body, declines with age, and is obtained through fermented foods and…
Does quercetin help with hay fever and allergies?
Quercetin has a clear anti-allergic effect in laboratory research, and a small randomised study in humans shows improvement in…
Preliminary evidence
What does quercetin do in your body?
Quercetin has interesting properties in the lab and in small human studies, but whether supplements actually make a difference…
How much taurine do you need per day?
There is no established daily figure for taurine alone. Anyone who regularly eats fish, meat or dairy is probably getting…
Preliminary evidence
How much magnesium do you need per day?
Research suggests that your body reaches balance at around 165 mg per day, but official recommendations are higher and there…
Moderate evidence
Do you need to restrict protein intake to protect your kidneys?
If your kidneys are healthy, you do not need to restrict your protein intake. If you have chronic kidney disease, discuss with…
Moderate evidence
Which fermented products help most for your gut health?
Yoghurt and kefir have the most human evidence supporting a beneficial effect on gut health; for kimchi, kombucha and tempeh,…
Moderate evidence
Is fermented food good for your health and your microbiome?
Fermented food, and kefir and yoghurt in particular, likely has beneficial effects on gut flora and several health markers,…
Yes · Moderate evidence
Which factors weaken your immune system?
Several factors demonstrably weaken your immune system: deficiencies in vitamin A, zinc, and iron are the best supported, but…
Can peptides contribute to muscle growth or recovery in older adults?
Peptides, especially in combination with resistance training, can make a measurable contribution to muscle mass and strength…
Yes · Moderate evidence
What are peptides and how do they work in the body?
Peptides are small protein fragments with a wide range of functions in the body, from hormones to defence substances. As a…
What is the TOTOX value of fish oil supplements?
Many fish oil supplements are more rancid than international standards allow and contain fewer active fatty acids than…
How do you prevent sarcopenia at older age?
Sarcopenia is the age-related loss of both muscle mass and muscle function and can be substantially slowed with resistance…
Moderate evidence
Which lifestyle habits protect your brain health over the long term?
Cognitive activities, a plant-based dietary pattern, and regular exercise, preferably in combination, offer the best-supported…
Moderate evidence
Does linoleic acid in tissue increase the risk of skin cancer?
There are preliminary indications that higher linoleic acid levels are associated with a higher melanoma risk, but the…
Preliminary evidence
Does omega-3 protect your skin from sunburn?
Omega-3 may offer some protection against sunburn reactions, but the evidence from good studies is too limited and no proven…
Yes · Moderate evidence
Can you permanently change your gut microbiome through diet?
Diet does indeed change your gut microbiome, but lasting change requires lasting adjustment of your dietary pattern; a…
Moderate evidence
Does a fasting-mimicking diet work better than simply eating less?
A fasting-mimicking diet has promising effects on several health markers, but whether it works better than simply eating less…
Moderate evidence
How much does ultra-processed food increase your risk of dying?
A high intake of ultra-processed food is associated with a higher risk of dying, but estimates vary widely (2% to 21%) and…
How many cups of green tea do you need per day?
Two to three cups of green tea per day is the amount at which research shows the most health benefits, though cause and effect…
Moderate evidence
How much CoQ10 do you need per day?
There is no established daily dose of CoQ10 for healthy people. The form on the label determines how much your body absorbs: a…
Insufficient evidence
How much iron do you need per day?
For healthy adults without a deficiency, 1 to 2 mg of iron per day through food is sufficient. When a deficiency or anaemia is…
Moderate evidence
How can you detect melanoma early?
The best way to detect melanoma early is to check your skin regularly, know the ABCDE features, and consult a dermatologist if…
Moderate evidence
Does eating a varied diet help your gut bacteria?
Fermented products have the strongest evidence base for increasing gut bacterial diversity. Eating broadly varied meals also…
Yes · Moderate evidence
What does stable blood sugar do for healthy ageing?
A stable, low blood sugar is associated worldwide with more healthy life years. The association is clear, but the exact gain…
Can you prevent dementia through your lifestyle?
Lifestyle does meaningfully influence your dementia risk: one third of all cases are linked to modifiable factors such as…
Yes · Moderate evidence
What keeps your memory sharp in later life?
Getting good sleep, eating mindfully according to the MIND diet and engaging in targeted cognitive training have the strongest…
Moderate evidence
Does the sleepy girl mocktail (magnesium with cherry juice) help you sleep?
Magnesium may make some difference for older adults with sleep problems or for people with a deficiency, but its effect has…
Preliminary evidence
Is beef tallow good for your skin?
There is no evidence that beef tallow works for skin complaints such as acne or eczema. The ingredients are not without value,…
Preliminary evidence
Does the fasting-mimicking diet, such as Prolon, actually work?
The fasting-mimicking diet improves measurable risk factors such as blood sugar, blood lipids and abdominal fat across…
Yes · Moderate evidence
Is fibermaxxing (eating as much fibre as possible) healthy?
Eating more fibre is well supported as healthy for most people, but overdoing it causes gastrointestinal complaints and no…
Yes · Strong evidence
Is raw milk healthier than pasteurised milk?
Raw milk offers no proven health advantages over pasteurised milk, while its infection risk is considerably higher. For…
No · Preliminary evidence
Does sulforaphane from broccoli sprouts work against ageing?
Sulforaphane has impressive effects on ageing processes in lab and animal studies, but whether this also holds true in people…
Preliminary evidence
Is sea moss (Irish moss) a worthwhile supplement?
As a food, sea moss has a reasonably good nutritional profile, but as a supplement there is no evidence that it provides a…
No · Preliminary evidence
Do you really need electrolyte supplements?
For most people who eat a normal diet, electrolyte supplements are not necessary. They are only useful during prolonged…
No · Moderate evidence
Is coffee healthy or unhealthy?
For most healthy adults, three to four cups of filter coffee per day, without sugar and cream, does more good than harm.…
Strong evidence
Are seed oils like sunflower oil bad for you?
Seed oils like sunflower oil are probably not outright harmful, but cannot be given an unconditional clean bill of health…
Moderate evidence
Does Red Orange Complex help against pigmentation spots and skin ageing?
There is positive evidence from multiple small human studies that 100 mg of red orange extract per day reduces pigmentation…
Yes · Moderate evidence
Which form of vitamin K2 is better: MK-4 or MK-7?
MK-7 is actually absorbed into the blood at normal supplementation doses, whereas MK-4 does not rise measurably at that dose.…
Moderate evidence
Is ubiquinol better than regular CoQ10?
Ubiquinol is not automatically better than regular CoQ10: the formulation, such as soft-gel or water-soluble, matters more…
Moderate evidence
Should you take extra copper when taking high doses of zinc?
Anyone who takes more than 25 mg of elemental zinc per day over a prolonged period runs a real risk of copper deficiency,…
Yes · Moderate evidence
Is it better not to take iron and calcium together?
For healthy people without medication, strictly separating intake is probably unnecessary, as long-term research shows no…
Moderate evidence
When is the best time to take fisetin?
There is no human research identifying an optimal time to take fisetin. What the available animal research makes clear is that…
Preliminary evidence
Is too much zinc harmful?
Too much zinc is certainly harmful: as an adult, stay below 25 mg of elemental zinc per day (EFSA limit) and be cautious with…
Yes · Moderate evidence
Can you get too much vitamin D?
Too much vitamin D is genuinely harmful, but that risk only arises at blood levels far above the recommended values. Stick to…
Yes · Moderate evidence
How much omega-3 with EPA and DHA do you need per day?
There is no fixed omega-3 dose for everyone: for heart protection, around 1 g of EPA+DHA per day is the most studied amount;…
Moderate evidence
How much vitamin D should you take per day?
For healthy adults under 75, extra vitamin D is probably not necessary. For children, adults aged 75 and over, pregnant women,…
Moderate evidence
How much curcumin should you take per day?
There is no fixed 'correct dose' of curcumin: for joint pain, less than 1000 mg per day works just as well as more, but for…
Preliminary evidence
Does eating less help you live longer?
In laboratory animals the effect on lifespan is well established, but in healthy humans direct evidence is lacking. A moderate…
Moderate evidence
Are ultra-processed products bad for your longevity?
Eating a lot of ultra-processed products is associated with a shorter lifespan and more chronic disease, but the effect varies…
Yes · Moderate evidence
How many vegetables do you really need per day?
Five servings of vegetables and fruit per day offers the best protection, with non-starchy vegetables counting and juice and…
Strong evidence
Is pterostilbene better than resveratrol?
Pterostilbene is absorbed better than resveratrol and more often outperforms it in laboratory and animal studies, but it has…
Preliminary evidence
Which type of collagen is best to take?
For the skin, hydrolysed collagen peptides (2.5 to 5 grams per day for at least 8 to 12 weeks) are the best-supported option.…
Moderate evidence
Which form of iron is best absorbed?
Haem iron from meat, fish and poultry is absorbed best. If you choose a supplement, divalent iron (ferrous sulfate) works…
Moderate evidence
Does the form of omega-3 you choose matter?
The form matters, but the meal you take omega-3 with matters at least as much: always take ethyl esters with a fatty meal,…
Preliminary evidence
Is it better to take magnesium in the evening?
Evening intake sounds logical given magnesium's role in melatonin and sleep, but no research directly compares evening versus…
Preliminary evidence
Is curcumin well absorbed by your body?
Ordinary curcumin without any addition is barely absorbed by the body; choose a product with piperine (black pepper extract)…
No · Moderate evidence
Is intermittent fasting good for longevity?
Intermittent fasting improves health markers such as weight and insulin sensitivity, but whether it also makes you live longer…
Moderate evidence
Why is muscle strength so important for healthy ageing?
Muscle strength is one of the best-supported pillars of healthy ageing: losing it increases the risk of falls, disability and…
Does walking do enough to maintain your muscles?
Walking alone is not enough to maintain muscle as you age. Add strength training and ensure adequate protein intake for the…
No · Moderate evidence
Can you regain lost muscle mass in later life?
Yes, regaining lost muscle mass in later life is possible, but the earlier you start, the better the outcome. Resistance…
Yes · Strong evidence
How much muscle strength do you lose per year after the age of fifty?
After the age of fifty, you can quickly lose 3 to 4% of leg strength per year, far more than muscle mass alone would suggest.…
Does alcohol increase your risk of cancer, even at one drink per day?
Yes, even one drink per day measurably increases cancer risk, particularly for breast cancer. No amount of alcohol has been…
Yes · Strong evidence
Does eating less red meat lower your risk of cancer?
Eating less red meat and processed meat probably lowers your risk of colorectal cancer; the association is strongest and best…
Yes · Strong evidence
Can you lengthen your telomeres through lifestyle?
Lifestyle can probably slow telomere shortening, but the starting length of your telomeres is largely genetically determined…
Yes · Moderate evidence
Does spending more time outdoors help your immune system as you get older?
Spending more time outdoors may support your immune system as you get older, mainly through improved vitamin D production, but…
Preliminary evidence
Can grip strength predict how long you live?
Grip strength is a remarkably strong predictor of longevity, stronger than blood pressure in some large studies. Whether…
What does a vitamin D deficiency do to your DNA?
A vitamin D deficiency is associated with greater DNA damage, especially in people with an additional risk factor. Make sure…
Can you drink coffee during intermittent fasting?
Black coffee fits comfortably within intermittent fasting and is explicitly listed as a fasting drink in dietary guidelines.…
Yes · Moderate evidence
Can an unhealthy diet cause puberty to start earlier?
A calorie-rich diet high in animal protein and low in fibre increases the likelihood of earlier puberty in girls, especially…
Yes · Moderate evidence
What does drinking coffee every day do to your gut bacteria?
Drinking coffee daily is associated with higher levels of beneficial gut bacteria such as Bifidobacterium and Bacteroides, but…
Can eating too little actually damage your cells?
Short-term eating less triggers a protective cellular clean-up process. If the restriction becomes too extreme or is…
Yes · Moderate evidence
Are there dietary patterns that have been proven to reduce bone fractures?
Fermented dairy, sufficient vegetables and fruit, and a varied diet with protein and calcium are best supported for bone…
Yes · Moderate evidence
Does bone broth help your gut health?
The individual components of bone broth, such as certain amino acids, show favourable effects on the intestinal wall in…
Preliminary evidence
Does fasting or calorie restriction make the skin look younger?
Fasting and calorie restriction appear to protect the skin in animal research, but direct evidence in humans that your skin…
Preliminary evidence
Do people with darker skin have a higher risk of osteoporosis (bone loss)?
People with darker skin have a greater chance of vitamin D deficiency, but that does not automatically mean greater bone loss.…
Moderate evidence
Can zinc contribute to stronger bones?
Getting enough zinc through your diet is probably important for your bone health, but whether a zinc supplement genuinely…
Preliminary evidence
Does astaxanthin help protect your skin from the sun?
Astaxanthin (4 mg per day, for at least 9 to 10 weeks) appears to give the skin some extra UV resistance, but should never…
Yes · Moderate evidence
Can you influence your epigenetic age through diet?
Multiple studies show that a healthy dietary pattern can favourably influence your epigenetic age, although these are…
Yes · Moderate evidence
Does a vegetarian diet weaken your bones?
A vegetarian diet does not automatically weaken your bones, but as a vegan you need to pay extra attention to calcium and…
Moderate evidence
What does too much or too little iodine do to your thyroid?
Both too little and too much iodine can disrupt the thyroid; make sure you get enough each day, but avoid large supplements…
Does sunbathing support your immune system beyond the vitamin D effect?
Sunlight influences your immune system beyond the vitamin D effect, through hormones, neuropeptides, and shifts in immune…
Yes · Moderate evidence
Is it true that artificial sweeteners cause cancer?
The vast majority of population research does not confirm a causal association between artificial sweeteners and cancer. There…
Does working with pesticides increase your risk of cancer?
Working with pesticides is associated in multiple studies with an increased risk of several types of cancer, including…
Yes · Moderate evidence
Does maintaining a healthy weight still help after a cancer diagnosis?
For most cancer types, a healthy weight after diagnosis is associated with better survival, but note: unintentional weight…
Yes · Moderate evidence
Does omega-3 from fish oil help with chronic inflammation?
Omega-3 from fish oil lowers inflammation markers in the blood and has the strongest evidence in rheumatoid arthritis. The…
Yes · Moderate evidence
Does eating flaxseed help your gut?
Through its fibre and lignans, flaxseed has a plausible positive effect on the gut, but for the gut as a specific target the…
Yes · Moderate evidence
Do lycopene and tomatoes protect against prostate cancer?
Processed tomato products are linked to a lower risk of prostate cancer, but whether lycopene is the cause is not certain.…
Moderate evidence
Does chronically poor air quality age your skin?
Chronic exposure to air pollution measurably accelerates skin ageing, and the evidence for this is reasonably consistent. If…
Does eating burnt food increase your risk of cancer?
Burnt or heavily grilled meat contains substances that cause cancer in animal studies, but whether ordinary exposure…
Preliminary evidence
What is DunedinPACE and what does it tell us about ageing?
DunedinPACE measures how quickly you are ageing biologically and is associated with disease and premature death, but the test…
Are there foods you should avoid eating before going to bed?
Alcohol, caffeine and fatty meals close to bedtime disrupt your sleep. You sleep better by avoiding all three in the evening…
Yes · Moderate evidence
Is soy good or bad for your bones after menopause?
Soy isoflavones probably do not protect the bones of postmenopausal Western women in any clinically meaningful way. It is…
Moderate evidence
Does dark skin age more slowly than light skin?
Dark skin ages visibly more slowly thanks to better UV protection, but is more prone to pigmentation. Sunscreen is the most…
Yes · Moderate evidence
What does fasting one day a week do to your gut microbiome?
Intermittent fasting demonstrably changes your gut microbiome, but the effects are likely temporary if you stop; for healthy…
Does fasting or intermittent fasting help prevent cancer?
There is no evidence that fasting prevents cancer in people. Results from animal studies are promising but contradictory. If…
Preliminary evidence
Does the timing of meals throughout the day affect your weight?
When you eat matters: meals earlier in the day appear more favourable for your metabolism than eating late, although the…
Yes · Moderate evidence
Does drinking a lot of coffee increase the risk of bone fractures?
For most people, coffee does not appear to be a proven cause of bone fractures. For women who drink a lot of coffee, some…
Moderate evidence
Does eating more fibre help against high blood sugar?
Water-soluble fibre from legumes, vegetables and fruit probably helps lower high blood sugar, but the overall composition of…
Yes · Moderate evidence
Does omega-3 (fish oil) have an effect on bone strength?
Omega-3 does not improve bone density in healthy older adults; for bone maintenance you are better off ensuring adequate…
No · Moderate evidence
Does eating gluten-free help if you don't have coeliac disease?
For healthy people without an established condition, there is no evidence that eating gluten-free provides any benefit, and it…
No · Moderate evidence
Is it true that a low-fat diet protects against breast cancer?
Simply eating less fat probably offers no demonstrable protection against breast cancer. Those who want to reduce their risk…
No · Preliminary evidence
What does alcohol do to your blood sugar and insulin sensitivity?
The effect of alcohol on your blood sugar depends strongly on context: on an empty stomach the risk of low blood sugar is…
Does boron as a supplement do anything for your bones?
Boron appears useful if you are not getting enough of it, but there is no good evidence that extra supplementation makes your…
Preliminary evidence
What are hormone disruptors, and are they really found in everyday products?
Hormone disruptors are demonstrably present in a great many everyday products and are measurable in the human body. Complete…
Strong evidence
Does omega-3 from fish or flaxseed help give you better-looking skin?
Omega-3 from fish oil has the strongest evidence base for skin conditions involving inflammation, such as eczema or psoriasis,…
Moderate evidence
What do polyphenols, such as those found in berries and red wine, do to your gut bacteria?
Polyphenols from berries and red wine have a positive influence on your gut bacteria, but the human studies are still small;…
Does eating from plastic packaging increase your risk of cancer?
There are indications that certain substances from plastic packaging, such as BPA and PCBs, are associated with a higher…
Preliminary evidence
Does drinking coffee really help against dementia, or is that a myth?
Drinking 2 to 3 cups of caffeinated coffee daily is associated with a lower dementia risk in several large studies, but this…
Moderate evidence
Does cinnamon really lower your blood sugar?
Cinnamon can modestly lower fasting blood sugar in type 2 diabetes, but whether that makes any meaningful difference to…
Moderate evidence
What does sunlight do for your bones, apart from vitamin D?
Sunlight helps your bones through vitamin D, but a separate bone benefit outside that pathway has not been demonstrated and…
Does a low-fat diet slow skin ageing or make it worse?
A low-fat diet is not necessarily better for your skin: the type of fat counts more than the amount, and monounsaturated fats…
Preliminary evidence
Are plant-based diets better for your gut than mixed diets?
A plant-based diet appears to be beneficial for your gut bacteria, but fermented foods perform at least as well in a direct…
Moderate evidence
Can you protect your DNA from damage through diet?
Diet can both protect and damage your DNA, but the protective effects of supplements often fall short in practice. Make sure…
Moderate evidence
Are there dietary patterns that have been proven to reduce your risk of cancer?
The Mediterranean diet and sufficient vegetables and fruit are consistently associated with a lower cancer risk, although the…
Yes · Moderate evidence
Does it matter for your weight whether you eat fat or carbohydrates?
In the long term, the ratio of fat versus carbohydrates matters little for your weight, as long as your total calorie intake…
No · Strong evidence
Does coffee dry out your skin?
Drinking coffee does not demonstrably dry out the skin; the research points more in the opposite direction. If you are…
No · Moderate evidence
Does the timing of your meals affect how well you sleep?
Eating late is associated with taking longer to fall asleep and poorer sleep quality, although cause and effect have not…
Does green tea help your gut health?
Green tea has shown measurable positive effects on gut bacteria and the gut wall in small studies, but the studies are too…
Preliminary evidence
Do carbonated drinks damage your bones?
Regularly drinking large amounts of sugary carbonated drinks is associated with lower bone density, especially in women and…
Yes · Moderate evidence
Can eating too little disrupt your hormones?
Even a temporary, substantial calorie deficit can disrupt sleep and reproductive hormones in healthy women; the timing of your…
Yes · Moderate evidence
Does green tea help improve your memory or concentration?
Green tea offers a modest but real benefit for concentration and working memory in healthy people, owing mainly to the…
Yes · Moderate evidence
Does bone broth actually do anything for your bones?
Animal and laboratory research shows positive signals, but there are no studies in humans. If you want to protect your bones,…
Preliminary evidence
Does urban pollution accelerate the ageing of your skin?
Urban pollution probably accelerates skin ageing, primarily through increased pigmentation spots and a weakened skin barrier.…
What is the difference between a high blood sugar and a blood sugar spike?
Fasting blood sugar and post-meal spikes are two separate quantities that you need both of for a complete picture; in diabetes…
What does magnesium do for your bone strength?
Getting enough magnesium appears to be good for your bones, but whether supplements truly prevent fractures has not yet been…
Does echinacea really work against the common cold?
Whether echinacea helps with the common cold depends strongly on which preparation you use. Standardised products made from…
Moderate evidence
Does the time you eat affect your ageing?
The time at which you eat does appear to matter, although the evidence in humans is still associative. A nightly fasting…
Yes · Moderate evidence
Is eating plant-based bad for your bones?
Eating strictly vegan is associated with lower bone density, but if you adequately supplement calcium and vitamin D, the…
Moderate evidence
Does taking vitamin D help against cancer?
If you already have sufficient vitamin D in your blood, extra supplementation probably does not help against cancer. If you…
No · Moderate evidence
What does intermittent fasting do to your insulin sensitivity?
Intermittent fasting improves insulin sensitivity in most people, but watch out for possible muscle loss and hormonal effects,…
Does intermittent fasting help your gut health?
For healthy people and people with metabolic syndrome there is reasonably consistent evidence that intermittent fasting has a…
Yes · Moderate evidence
Does passive smoking (secondhand smoke) increase your risk of cancer?
Passive smoking increases your risk of cancer, with the strongest evidence for lung cancer. The risk is real but smaller than…
Yes · Moderate evidence
Does fasting or eating less help your memory and concentration?
Eating less or intermittent fasting probably shows a small positive effect on memory and concentration. The evidence is there,…
Yes · Moderate evidence
What does a low-carbohydrate diet do to your LDL cholesterol?
A low-carbohydrate diet raises LDL cholesterol modestly in most people, and sometimes substantially. If you already have…
Can you preserve your fertility as a woman for longer through your lifestyle?
Studies show that a healthy weight is measurably linked to better fertility. Whether changing your lifestyle actively…
Moderate evidence
Does green tea protect against cancer?
Drinking green tea is safe and people who drink it develop cancer slightly less often, but whether the tea itself is the cause…
Moderate evidence
Does eating a lot of sugar increase my risk of cancer?
Drinking large amounts of sugary drinks is associated with a noticeably higher risk of certain cancers, especially early-onset…
Yes · Moderate evidence
Does olive oil protect your brain from decline?
Extra virgin olive oil as part of the Mediterranean diet has been linked to less cognitive decline in multiple studies, but…
Yes · Moderate evidence
Does the order in which you eat your food matter?
Eating vegetables and/or protein first and carbohydrates last demonstrably blunts the post-meal blood sugar spike, even in…
Yes · Moderate evidence
Does green tea help against infections?
For flu there is reasonable evidence that green tea catechins help; for most other infections the evidence is still limited to…
Moderate evidence
Does eating garlic help your gut health?
Garlic shows some signs of improving gut function in people, although the evidence is limited. The best-supported finding is…
Preliminary evidence
Do your cells actually get younger when you restrict calories?
Calorie restriction demonstrably slows the biological rate of ageing in cells, including in people. An approach such as the…
What does smoking do to your brain as you age?
Smoking accelerates brain ageing and increases the risk of dementia. Quitting smoking is one of the best-supported steps you…
Why do you get sick more often when you are on a diet?
A low-calorie diet can weaken your immune system through deficiencies in minerals such as magnesium, disrupted gut bacteria…
Is brown fat really different from regular fat, and can I activate it?
Brown fat is genuinely different from regular fat and you can activate it, with cold exposure having the strongest evidence.…
Yes · Strong evidence
Does drinking coffee protect against liver cancer?
Drinking coffee is consistently associated with a lower risk of liver cancer, and that association is better supported than…
Yes · Strong evidence
Are short bursts of movement better than one long walk?
For fitness and day-to-day blood sugar control it makes little difference whether you exercise in spread-out bouts or in one…
Moderate evidence
How much impact does smoking have on your bone density?
Smoking substantially increases the risk of bone loss and hip fractures; quitting helps, but it takes at least ten years…
Can your gut microbiome influence how long you live?
There are clear indications that the composition of your gut microbiome is associated with how long and how healthily you age,…
Moderate evidence
What does caffeine do to your memory and concentration in the long run?
Caffeine helps you stay more alert and focused when you are tired, but it does not make a well-rested brain smarter. If you…
Does the type of protein you eat matter for muscle building?
The type of protein matters per meal for muscle building, but over the long term with resistance training, the difference…
Yes · Moderate evidence
Which foods improve your insulin sensitivity?
Diet can clearly improve your insulin sensitivity. The Mediterranean diet has the strongest evidence base, but the timing and…
Strong evidence
How much protein can your body use in a single meal?
Your body can use more than 20-25 grams of protein per meal, especially when that protein is combined with carbohydrates and…
Does extra protein help with losing weight without losing muscle?
Extra protein helps preserve muscle mass while losing weight, but works best in combination with strength training. Aim for…
Yes · Strong evidence
When is the best time to eat protein for your muscles?
Distribution throughout the day matters most: eat a portion of 20-40 g of protein every 3 to 4 hours, and the precise timing…
Do older adults need more protein than younger people?
Older adults likely need more protein than the standard guideline of 0.8 grams per kilogram suggests. As a healthy older…
Do proteins inhibit your autophagy?
Proteins inhibit autophagy because amino acids from your meal keep mTOR active, the best-known brake on autophagy. If you want…
Yes · Moderate evidence
What is a healthy ApoB level?
There is no fixed 'healthy' ApoB value, but below 82 mg/dL the risk of a stroke already decreases measurably. ApoB offers…
Which foods or habits effectively raise NAD+ levels?
Exercise and NAD+ supplements (NR or NMN) demonstrably raise NAD+ levels, but whether higher levels also confer health…
Moderate evidence
What are the Blue Zones, and what is actually true about them?
Blue Zones show a striking pattern of lifestyle and advanced age. The exact age figures are disputed, but regular exercise,…
Moderate evidence
Which foods or supplements keep your blood vessels healthy?
The Mediterranean diet most demonstrably lowers your risk of heart and blood vessel disease. Individual supplements do not help.
Moderate evidence
Can you delay menopause with lifestyle or diet?
Avoiding smoking, eating less red meat, and eating more citrus fruit and oily fish appear to have a favourable influence on…
Preliminary evidence
What causes age spots and can you prevent them?
Years of sun exposure is the clearest cause of age spots. Consistent sun protection is the smartest prevention; for existing…
Moderate evidence
Does drinking lots of water really help against dry skin and wrinkles?
Drinking more water has no proven effect on wrinkles and does very little for dry skin. A moisturising cream is a better…
No · Preliminary evidence
Is yo-yo dieting, repeatedly gaining and losing weight, bad for me?
Yo-yo dieting is probably less harmful than is often thought, but whether it is the cause of health damage, or whether…
Moderate evidence
Does eating a lot of sugar give you type 2 diabetes?
Sugary drinks clearly and demonstrably raise your risk of type 2 diabetes. Sugar from solid food barely does. The biggest…
Does it make sense to limit blood sugar spikes, even without diabetes?
Limiting blood sugar spikes makes sense even without diabetes: the risk of cardiovascular disease appears to rise with spikes…
Yes · Moderate evidence
How much calcium do I need per day, and can too much be harmful?
Calcium requirements range from 800 mg (young children) to 1500 mg per day (older adults, teenagers, postmenopausal women). Up…
Strong evidence
Does avoiding coffee in the afternoon really help my sleep?
Whether an afternoon cup disrupts your sleep depends strongly on how much you drink. One cup, approximately 100 mg of…
Moderate evidence
Does the MIND diet help against dementia and cognitive decline?
Large studies in people link the MIND diet to a lower chance of dementia, but the only large study in which people were…
Moderate evidence
How do I keep my eyes healthy and prevent cataracts or macular degeneration?
Protect your eyes with UV-filtering glasses, a diet rich in vegetables and fruit, good diabetes management and regular eye…
Moderate evidence
Is farmed fish just as healthy as wild fish?
Three to four portions of fish per week is healthy for most people. Whether farmed fish and wild fish are nutritionally…
Strong evidence
Does it matter what time of day I eat?
Eating earlier in the day is more favourable for your weight, blood sugar and hormone balance than eating late or at night.…
Yes · Moderate evidence
Are smoothies and fresh juice just as healthy as whole fruit?
Whole fruit comes out ahead of fruit juice: more fibre, greater satiety, and fewer free sugars. Smoothies fall somewhere in…
No · Moderate evidence
Is wholegrain bread really that much better than white bread?
Large-scale observational research consistently points in the same direction: wholegrain is better for your heart, your weight…
Yes · Moderate evidence
Do you live longer on a vegetarian or plant-based diet?
A good-quality plant-based diet is linked to fewer early deaths. But strictly vegetarian or vegan eating has not been proven…
Moderate evidence
How many fruits and vegetables do I actually need per day?
Five portions of fruit and vegetables per day (two pieces of fruit, three serving-spoon scoops of vegetables) is the number…
How much rest do my muscles need between workouts as I get older?
Getting older does not call for more rest, but for more regular training: at least two resistance-training sessions per week,…
Moderate evidence
Does taking vitamin E have any proven benefit?
For the most widely studied application, the heart, vitamin E demonstrably does not work; for skin and fertility the evidence…
No · Strong evidence
Is taking a stack of supplements at the same time dangerous?
Whether a supplement stack is smart or dangerous depends on which substances you combine and whether you also take medicines.…
Moderate evidence
Does vitamin C actually help against a cold?
Taking vitamin C daily does not protect most people against colds, but does make a cold somewhat shorter and milder. Intensive…
No · Strong evidence
Does eating enough protein help my immune system as I get older?
Eating enough protein helps your immune system in later life. Aim sustainably for at least 1.0 to 1.2 grams per kilogram of…
Yes · Moderate evidence
Does eating a high-fibre diet help against constipation as you get older?
Eating more fibre helps with constipation in older adults, but the overall dietary pattern matters at least as much as fibre…
Yes · Moderate evidence
Does my gut microbiome change as I get older, and does it matter?
Your gut microbiome certainly changes as you get older, but whether that is harmful depends strongly on which direction that…
Yes · Strong evidence
Do you actually live longer if you structurally eat fewer calories?
In laboratory animals, eating less convincingly extends lifespan, but this has not yet been demonstrated for healthy people…
Moderate evidence
From how much alcohol do I actually face a higher risk of cancer?
Even with light drinking your risk of mouth, throat, oesophageal and breast cancer is already measurably higher. A safe lower…
Does mentally challenging work protect against dementia?
Studies following people for years consistently show that mental challenge lowers the risk of dementia, but this is an…
Yes · Moderate evidence
Does everyone age at the same rate?
At the molecular level everyone ages at a broadly similar baseline rate, but in terms of health and life expectancy people can…
What does my CRP value (inflammation) say about my heart?
A high hsCRP value points to chronic inflammation and predicts a clearly elevated long-term risk of cardiovascular problems,…
Does drinking less alcohol meaningfully reduce your cancer risk?
Drinking less alcohol meaningfully reduces your risk of several cancer types, although it takes years before the full effect…
Yes · Strong evidence
Does red and processed meat really increase your risk of colorectal cancer?
Multiple large studies consistently show that high consumption of red meat, and especially processed meat, raises the risk of…
Which lifestyle factors reduce your cancer risk the most?
Not smoking, a healthy weight, regular exercise and little or no alcohol have the strongest and best-supported protective…
Strong evidence
Does sugar accelerate skin ageing through glycation?
The biological mechanism is rock solid: chronically high blood sugar levels accelerate the breakdown of collagen and elastin…
What do smoking and alcohol do to the ageing of your skin?
Smoking demonstrably accelerates skin ageing: it damages your skin cells from within and causes inflammation. For alcohol…
Does eating a high-fibre diet help protect against colorectal cancer?
Eating more fibre, especially through whole grains, is consistently associated with a lower risk of colorectal cancer. Whether…
Yes · Strong evidence
Does too little protein increase your risk of bone fractures as you get older?
Yes, too little protein increases your risk of bone fractures in later life. This works both through weaker bones and through…
Yes · Moderate evidence
Do calcium and vitamin D supplements really help against bone loss?
Calcium and vitamin D together can improve bone density and slightly reduce the risk of hip fractures when a deficiency has…
Moderate evidence
Does fermented food such as yoghurt, kefir and sauerkraut help your gut microbiome?
Fermented foods, and kefir and yoghurt in particular, have the strongest clinical support for a positive effect on the gut…
Yes · Moderate evidence
What do fibres do to your gut microbiome?
Fibre demonstrably feeds your gut bacteria, improves stool consistency and protects the gut wall. But how your microbiome and…
Does quercetin work against ageing and inflammation?
Quercetin shows promising signals in the laboratory and in animals, but in humans there is not yet solid evidence. Taking…
Preliminary evidence
Is taking extra vitamin C worthwhile?
Extra vitamin C offers little benefit for most people. Intensive athletes and people following a carnivore diet do have a good…
Moderate evidence
Does ginger help with inflammation and nausea?
Ginger probably helps with nausea, especially during chemotherapy and possibly also after surgery or during pregnancy. For…
Yes · Moderate evidence
Is eating organic food really healthier?
Eating organic probably does not give you better nutritional value, but it does lower your exposure to pesticide residues and…
Moderate evidence
How much water do I really need to drink per day?
There is no magic number: for a healthy adult who is not very active, thirst is a reliable guide, with a total fluid intake of…
How many years does smoking cost me, and does quitting still help?
Smoking demonstrably costs years of life expectancy at the population level, but a precise personal figure cannot be given on…
Moderate evidence
How much sugar is too much?
There is no universal threshold, but for tooth decay, getting less than 10% of your daily calories from free sugars is the…
How much fibre do I need and why?
Aiming for 25 to 29 grams of fibre per day is well supported and delivers the greatest health benefit. Most people in Western…
Moderate evidence
Is intermittent fasting worth it?
Intermittent fasting helps with weight loss and improves blood glucose and insulin, but over the longer term it does no better…
Yes · Moderate evidence
What can I do myself to lower my risk of cancer?
By not smoking, limiting alcohol, maintaining a healthy weight, and moving enough, you can meaningfully lower your risk of…
Moderate evidence
Which diet is best supported by evidence for a long, healthy life?
For anyone looking to use diet to invest in a long and healthy life, the Mediterranean diet is currently the best-supported…
Moderate evidence
Which screenings and check-ups are recommended for my age?
Which screenings apply at your age depends on the individual, but a few anchor points are well supported: annual mammography…
Moderate evidence
Do antioxidant supplements make sense?
For healthy people, antioxidant supplements such as beta-carotene and vitamin E are not useful as protection against cancer or…
No · Strong evidence
Is soy healthy, or not because of the phytoestrogens?
Soy is probably harmless and possibly beneficial for most healthy adults, but caution is advised for children with thyroid…
Moderate evidence
How healthy are yoghurt and dairy for your heart and bones?
Yoghurt and dairy are a perfectly good choice for bone health for most people, and are likely neutral to mildly beneficial for…
Is a low-carbohydrate or ketogenic diet good for living longer?
A ketogenic diet can help with weight problems and metabolic disorders, but for people who simply want to live longer and stay…
Preliminary evidence
Does garlic help against high blood pressure or high cholesterol?
Garlic supplements measurably lower blood pressure in people with hypertension and have a modest favourable effect on…
Yes · Moderate evidence
How harmful is too little daylight or sunlight?
Too little sunlight is demonstrably harmful, especially for your bones. For broader disease risks the associations are…
Which health checks are genuinely worthwhile and which are a waste of money?
Cervical cancer screening (ages 21-65) and lung cancer screening (ages 50-80, 20+ pack-years) have the strongest evidence base…
Moderate evidence
Should I take vitamin B12 supplements as I get older?
Getting older increases the risk of a B12 deficiency, even if you eat healthily. A tablet of 1000 µg per day is safe and…
Yes · Moderate evidence
Does ashwagandha really work against stress?
Ashwagandha demonstrably lowers the stress hormone cortisol, but whether it also makes you actually feel less stressed has not…
Moderate evidence
Does turmeric help against inflammation?
Curcumin has a biologically plausible anti-inflammatory effect, but the clinical results are mixed. If you want to try it,…
Moderate evidence
Is eating a lot of protein bad for your kidneys?
For people with healthy kidneys there is little reason to worry about a generous protein intake, but those who have kidney…
Moderate evidence
Are beans and legumes good for a long life?
Many large studies in people consistently point in the same direction: eating more legumes is linked to a lower risk of dying.…
Yes · Moderate evidence
Does dark chocolate or cocoa benefit your heart?
Dark chocolate with a high cocoa content appears to be good for your heart, but the evidence is still based on studies that…
Yes · Moderate evidence
Does eating fish help your heart and your brain?
Two portions of oily fish per week, as part of a varied and plant-rich diet, is a smart choice for most people when it comes…
Yes · Moderate evidence
How healthy is olive oil and what is it good for?
Olive oil, and extra-virgin olive oil in particular, is well supported as protective for the heart and blood vessels,…
Does coffee help protect against type 2 diabetes?
People who habitually drink three to five cups of coffee a day are consistently less likely to develop type 2 diabetes in…
Yes · Strong evidence
Are eggs bad for your cholesterol?
Eggs are not automatically bad for your cholesterol; the rest of your diet, especially the amount of saturated fat, carries…
Moderate evidence
Are diet soft drinks and sweeteners bad for you, and if so, why?
Studies where people were assigned to a sweetener or comparison drink show that diet soft drinks at moderate consumption are…
Moderate evidence
Does eating processed meat such as sausage and ham give me colorectal cancer?
Eating a lot of processed meat measurably raises your risk of colorectal cancer by around 18-21%. Eating less sausage and ham,…
Yes · Strong evidence
How bad is ultra-processed food, and what does it do to you?
Eating a lot of ultra-processed food is consistently associated with higher risks of cardiovascular disease, diabetes,…
Does the Mediterranean diet help you live longer?
In large population studies, the Mediterranean diet is consistently linked to a lower chance of dying and less heart and blood…
Yes · Strong evidence
Do fish oil pills keep my memory sharp?
Fish oil may make a modest contribution to attention and memory, but the evidence is not strong enough to recommend a pill…
Moderate evidence