I like to cook with olive oil. As part of the Mediterranean diet, it can be used as a replacement for other fats in the diet. Is it a good idea to use it to promote longevity and reduce the risk of death from other diseases? According to an article in Reader's Digest, it is beneficial to take it directly from the bottle or use it in cooking. A Harvard study shows that olive oil can be a miracle drug. The study only showed correlation and not cause and effect.

The study was published in a journal. The Nurses Health Study and the Health Professionals Follow-up Study were used to conduct the study. Over the course of 28 years, participants answered questions about their use of olive oil for salad dressing, baking, frying, sauteing, and spreading on bread, as well as their use of other vegetable oils and dairy fat. The causes of death for people in the highest quartile of olive oil consumption were calculated by the researchers.

There were results.

There were 36,856 deaths during that time. People who drank the most olive oil were less likely to die. They were less likely to die of cardiovascular disease, cancer, neurodegenerative diseases, and respiratory diseases.

Sometimes correlation does not mean causality. Occasionally, it does. The number on the scale is related to the number of apples added to it. When there is no link, correlation can be mistaken for causality. The size of a child's vocabulary is related to their shoe size. A simplistic interpretation suggests that wearing bigger shoes will lead to a bigger vocabulary. It doesn't mean that putting on Daddy's big shoes will make children understand the meaning of big words like "Gigantopithecus" The relationship doesn't involve shoe size.

The study received criticism.

Dahms reviewed the study. He was skeptical of the results because of the inaccuracy of self-reporting, the impossibility of controlling for all possible confounders, and the fact that participants were not representative of the entire population. The Spanish PREDIMED study had an average intake of more than 20 grams. He wondered if another vegetable oil might show the same results, and if some component of olive oil might be to blame. He can't recommend anything other than to replace animal fats with healthier fats.

He found reason to be optimistic.

 Perhaps more surprising was the comparison between the second quartile of the olive oil intake and the lowest quartile (rare/no olive oil intake), which showed a 12% reduction in mortality risk from all causes at the intake level of just 0.5 teaspoon or about 1.5 g/day of olive oil. If this finding is borne out in further studies, that’s an amazing benefit from an astonishingly low level of olive oil consumption. Another promising finding was a 27% reduction in risk of dementia-related mortality for those in the highest versus lowest category of olive oil consumption, which, considering the lack of proven preventatives for Alzheimer’s disease and dementia, could be of great importance from a public health perspective.

Food and not medicine is the conclusion.

There is a place in the kitchen for olive oil. The evidence is not strong enough to justify re-classifying olive oil as a medicine or taking it every day to live longer.