As I mentioned the inflammatory response gets mobilised anytime there is damage to the body. Unfortunately the body is under constant low level oxidative damage all the time from free radicals. These free radicals are nasty little unstable molecules that fly around stealing electrons from cells and generally causing havoc. The body’s defence to these free radicals are antioxidants; antioxidants are able to safely donate their electrons to the free radicals rendering them safe. The main source of antioxidants in our body is from the foods we eat, foods that contain nutrients such as amino acids, vitamin A, vitamin C, vitamin E, zinc, selenium and many other compounds such as alpha lipoic acid, green tea extract and carotenes.
The classic heart disease theory looks a little like this:
• Too much cholesterol in the diet causes cholesterol to be deposited in the arteries, such as the coronary arteries.
• Cholesterol deposited in the coronary arteries causes narrowing or blocked arteries and hey presto a heart attack.
A novel approach to heart disease involving inflammation looks like this:
• A poor diet lacking in antioxidants leads to poor protection from free radicals and oxidative damage.
• As cholesterol travels though the arteries it moves in and out of the vascular endothelial cells(the intima).
• Cholesterol is attacked by free radicals and becomes damaged “oxidised cholesterol”.
• Oxidised cholesterol is not recognised by the by the immune system which mounts an inflammatory reaction whereby immune cells called macrophages come along and eat the oxidised cholesterol.
• The macrophage that has eaten the damaged cholesterol becomes a foam cell that is now trapped inside the endothelial cells that line the walls of the arteries.
• As these foam cells build up they cause narrowing of the artery and can lead to reduced blood flow to the heart muscle.
• Hey presto a heart attack.
So cholesterol just seems to be the innocent bystander of the oxidative damage caused by a diet lacking antioxidants.
Consider these couple of studies to highlight the point:
The JUPITER study in 2008 investigated 17,000 people considered to be at risk for heart disease. This trial assessed whether the statin drug Crestor could prevent heart disease in healthy individuals with low LDL-cholesterol levels but elevated CRP (a marker for inflammation).
The study found “unequivocal evidence of a reduction in cardiovascular morbidity and mortality (about 40%) among those treated with the statin compared with placebo”. However what mechanism was at work? We know that the study group had low cholesterol so was lowering it even more what helped, or do statins lower CRP and prevent heart disease by reducing inflammation?
Another study called The Lyon Diet Heart Study investigated 600 people who had survived a first heart attack and were at high risk of another. The authors divided the people in to one of two groups:
• Group 1 received no dietary intervention.
• Group 2 received advice to follow a Mediterranean diet (More on this later).
What were the results? Well, as with the JUPITER trial, The Lyon Diet Heart Study was also stopped early because those following the Mediterranean diet had such a significant reduction in recurrent heart attacks that the authors were ethically compelled to put everyone on a Mediterranean diet. After 4 years, those still following a Mediterranean diet had a 50-70% lower risk of recurrent heart attacks! Now here is the biggest shock – neither group had a change in cholesterol levels. So cholesterol could not the determining factor. What was? We can’t say for sure but a Mediterranean diet is a lot less inflammatory than a conventional Western diet.
Compare the results of The Lyon Diet Heart Study (50-70% lower risk of recurrent heart attacks) to the JUPITER study where those taking a drug only had a 40% reduction in cardiovascular morbidity and it’s quite plain to see that making significant changes in your diet and lifestyle are far more effective for preventing heart disease than taking drugs.
The Mediterranean diet
The Mediterranean diet is generally considered to be the native diet of the inhabitants of Crete from between 1945 to 1970. It consists of the following foods:
• Abundant in plant food (fruits, vegetables, pulses, beans and lentils, whole grains, nuts and seeds)
• Fresh fruit as the typical daily dessert
• Olive oil as the principle source of fat
• Saturated fat less than 8% of total calories
• Moderate dairy products mainly cheese and yoghurt
• Moderate fish, lamb and poultry
• Moderate wine consumption 1-2 glasses a day
• Less than 2000 calories a day
This diet may be moderate to low in saturated fat, but it is high in omega 3 fats, fibre and antioxidants that help prevent inflammation. More on how important omega 3 fats are in the coming blog posts.
