Q: What is the healthiest oil to
cook with?

– Rebecca, Sheffield

A: Olive oil is rich in monounsaturated fats — the kind that help reduce “unhealthy” LDL cholesterol and boost “healthy” HDL cholesterol. And new research suggests that virgin (and extra-virgin) olive oils — those produced purely by mechanically pressing the oil from olives, with no chemical processing — have an edge: antioxidants called polyphenols. Naturally found in olives (in red wine and green tea too), polyphenols mop up free radicals before they can oxidize LDL (oxidation makes LDL even more damaging to arteries).

In a three-week study of 200 men published recently in Annals of Internal Medicine, those who consumed just under two tablespoons a day of high-polyphenol virgin olive oil in place of other dietary fats registered larger increases in “good” HDL cholesterol and fewer markers of oxidative stress than men who consumed the same amount of “ordinary” olive oil, which had a very low polyphenol content. Chemical refining processes remove some polyphenols from “ordinary” olive oils (often labeled as “pure” in the U.S.) and other cooking oils, say researchers at the Municipal Institute for Medical Research in Barcelona, Spain.

Virgin olive oil doesn’t just taste better than plain old “olive oil,” it’s better for you too. Buy organic virgin olive oil where possible.

Q: I hear conflicting reports about how many eggs we should eat. What’s the truth?

A: In the past, health experts thought that egg’s high cholesterol content might endanger heart health. But in recent years several studies have shown that egg consumption does not necessarily raise blood cholesterol or increase risk of heart disease.

Current heart-related nutrition recommendations still encourage limiting eggs to no more than four or five a week, especially the yolk, which raises health concerns. But it is clearly much more important to limit foods high in saturated fats (fatty meats and dairy products) and trans fatty acids (margarine and commercial baked goods, cakes, biscuits and deep-fried foods).

When it comes to cancer risk, a landmark report from the American Institute for Cancer Research (AICR) notes that a high intake of eggs or cholesterol could possibly the increase risk of some forms of cancer, but many other aspects of what we eat have a much greater influence on cancer risk. Set your priorities on an unsaturated fat, whole grain and plant-based diet. Eggs are an inexpensive source of protein and other nutrients, and they don’t send your blood cholesterol soaring, if you enjoy them in moderation.

Making walnuts part of a balanced diet can help counteract the damage to arteries caused by fatty food new research says.

Over time fat molecules harden the arteries leading to heart disease. But walnuts contain a nutrient that helps the body produce nitric oxide —which helps keep blood vessels flexible. In tests, 24 healthy adults were fed high fat meals with either olive oil or eight shelled walnuts. Both helped to reduce the inflammation of arteries that follows a meal high in fat and leads to hardening. But walnuts were also found to help preserve elasticity and flexibility of blood vessels.

Walnuts contain arginine which is used by the body to produce nitric oxide. They also provide a form of omega 3 which is not found in olive oil.