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, especially when used in place of butter and as part of a varied, plant-based diet.
Olive oil has been most thoroughly studied for its role in protecting the heart and blood vessels. Large studies, including the PREDIMED trial and dozens of cohort studies involving tens of thousands of participants, consistently show that a Mediterranean diet with extra-virgin olive oil as the primary fat source clearly reduces the risk of heart attack, stroke, and death from heart disease. This is the strongest evidence available regarding olive oil.
Olive oil on its own also appears to have an effect: an American study following more than 221,000 people for up to 33 years found that each additional teaspoon of olive oil per day was associated with an 8% lower risk of early death. Replacing butter with vegetable oils was also linked to 17% fewer deaths from cancer. These are observational associations, however: people who consume a lot of olive oil may also live more healthily in other ways. Nevertheless, the association is remarkably consistent.
For cholesterol, extra-virgin olive oil appears to have a modest but positive effect: it likely lowers LDL cholesterol (the 'bad' cholesterol). The certainty of this evidence is moderate, not high. There are also some indications for blood sugar regulation, but these are too weak to draw serious conclusions from.
Olive oil contains plant compounds (polyphenols) that have shown anti-inflammatory and antioxidant effects in laboratory and early clinical research. Whether those effects also translate meaningfully into the body under normal eating habits has not yet been firmly established. There are also early indications that olive oil may beneficially influence the gut microbiome, which could in turn be good for the brain, but this research is still very much in its early stages.
Important to know: the evidence is strongest for extra-virgin olive oil as part of an overall dietary pattern, together with vegetables, fruit, nuts, legumes, and fish. Treating olive oil as a standalone miracle remedy overstates what the science actually shows. Use it as a replacement for butter or saturated fats, not as an addition on top of an unhealthy diet.
Claims are based on multiple large cohort studies (>221,000 participants), the PREDIMED trial, systematic reviews, and mechanistic studies. Observational associations predominate; causal claims are strongest for the Mediterranean diet as a whole.
Does taking omega-3 help you stay healthy for longer?
Omega-3 reliably lowers blood fats, but the evidence that it helps you live longer or stay healthier is limited. If you already have heart disease, discuss with your doctor whether omega-3 is a worthwhile addition to your treatment.
What is a healthy cholesterol level and when should I be concerned?
A normal LDL value does not give a complete picture of your cardiovascular risk. Ask your doctor about your remnant cholesterol as well, especially if cardiovascular disease or Alzheimer's disease runs in your family.
What is a healthy HDL (good cholesterol) level, and can I raise it?
Raising HDL through lifestyle is possible, but your genes set the ceiling. Lowering triglycerides through less sugar and alcohol, more exercise, and weight reduction has the greatest effect.
Is the Mediterranean diet really good for your heart, and why?
For people at increased heart risk, the Mediterranean diet is the best-supported dietary choice currently available. Both large studies in people and dozens of population studies confirm a lower risk of heart attack and stroke.
Is green tea really as healthy as they say?
Two to three cups of green tea a day fits well into a healthy lifestyle and is probably safe, but do not take concentrated green tea extracts as a supplement: they can damage your liver.
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 more weight. If you have high LDL, diabetes or a family history of cardiovascular disease, discuss your egg consumption with your doctor.