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. Cheese follows at a reasonable distance; for kefir, the evidence from studies in people remains limited.
Yoghurt and fermented milk have the strongest support. People who eat yoghurt regularly are about 27% less likely to develop type 2 diabetes and about 20% less likely to develop metabolic syndrome. Fermented milk is linked to a small reduction in the risk of stroke, heart and vascular disease, and cardiovascular death (roughly 4%). These are associations measured in people followed for many years; that yoghurt is the cause has not yet been proven.
Cheese shows a slightly reduced risk of death from any cause, dementia, bone fractures, and type 2 diabetes in large long-term studies. The reductions are modest: 5 to 19 percent. For other conditions, such as prostate cancer or high blood pressure, no difference was found.
Kefir is widely discussed, but studies in people are largely absent. Experiments with cells and animal studies show bacteria-fighting and immune-supporting effects. Whether that translates into a benefit for you at home is still unclear. Artisanal and industrially produced kefir also differ considerably in composition.
All fermented foods share a few practical advantages: fermentation breaks down lactose, phytic acid, and some harmful compounds, boosts antioxidant activity, and can slightly increase vitamin content. The living micro-organisms they contain may influence the gut microbiome, although this varies greatly from product to product and from person to person. That fermentation produces blood-pressure-lowering compounds has been described, but whether this leads to a measurable drop in blood pressure in people has not yet been convincingly demonstrated.
The evidence rests on large studies in which people were followed for many years, supplemented by several summary reviews and two analyses combining many studies. The evidence is most fully developed for yoghurt and cheese. For kefir, only results from experiments with cells and animal studies are available. The authors of the kefir combined-studies analysis themselves caution that the results should be interpreted carefully, because the studies examined differed considerably from one another and used different bacterial strains. This makes the findings on kefir less reliable.
What are the benefits of fermented foods?
Fermented foods show real benefits for antioxidant activity and digestibility, and there are indications that they may support resistance to infection. For claims around mental health and ADHD, the research is still too limited to draw any meaningful conclusions.
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 choice. Large human studies consistently show positive effects on both cardiovascular health and cognitive health.
Is eating organic food really healthier?
Eating organic demonstrably leads to lower pesticide exposure and less contact with antibiotic-resistant bacteria through meat. Whether this translates into less disease in the long run remains unclear.
Is raw milk healthier than pasteurised milk?
Research shows that pasteurised milk provides almost the same nutrients as raw milk. The vitamin loss from heat treatment is small.
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 additional benefit has been demonstrated. Aim for 25 to 29 grams per day through regular food intake.
Are smoothies and fresh juice just as healthy as whole fruit?
Whole fruit and fruit juice may look similar, but research shows they do not have the same effect on your blood pressure.