f factors turns out to be even more indicative of CVD 20, 21, 22, 23.
One of the most interesting aspects of this finding from our perspective, is that the ratio of triglyceride levels to HDL is considered to be a surrogate marker of insulin resistance (See The Ketogenic Diet as a Treatment for Metabolic Syndrome.) In other words, the best lipid predictors of CVD are also those that indicate insulin resistance.
Ketogenic Diets improve risk factors for CVD
There is now ample evidence that a low carbohydrate, ketogenic diet improves lipid profiles, particularly with respect to the risk factors outlined above: triglycerides, HDL, and their ratio 24, 25, 26, 27, 28, 29, 30, 31.
Although a ketogenic diet typically raises LDL levels, which has been traditionally seen as a risk factor, it has also been shown to improve LDL particle size. In other words, although the absolute amount of LDL goes up, it is the "good" LDL that goes up, whereas the "bad" LDL goes down 31, 32. This is hardly surprising, since LDL particle size is also strongly predicted by triglycerides 33, 34, 35.
Although there have not yet been intervention studies testing the effect of a ketogenic diet on the rate of actual CVD incidents (e.g. heart attacks), the evidence about lipid profiles is strong enough to make ketogenic diets more likely to reduce heart disease than any other known intervention.
- Current medical practice uses blood lipid measurements to assess the risk of heart disease.
- Despite the continuing tradition of measuring total cholesterol and LDL, we have known for decades that triglycerides, HDL, and the ratio of the two, are much better predictors of heart disease. LDL particle size is also considered strongly predictive.
- A ketogenic diet has a very favourable impact on these risk factors, and thus should be considered the diet of choice for those at risk of CVD.
In their 2011 paper, "Low-carbohydrate diet review: shifting the paradigm", Hite et al. display the following graph (VLCKD stands for Very Low Carbohydrate Ketogenic Diet, and LFD for Low Fat Diet) 36 based on data from 31:
It makes an excellent visualization of the factors at stake, and how powerful a ketogenic diet is. It also shows quite clearly that not only is restricting carbohydrate more effective for this purpose than a low fat diet, but that a low fat diet is detrimental for some important risk factors — apolipoprotein ratios, LDL particle size, and HDL — but a low carb diet is not. The ketogenic diet resulted in a significant improvement in every measure.
1 Evidence type: observational
World Health Organization Fact sheet N°317: Cardiovascular diseases (CVDs) September 2011
2 Evidence type: observational
- CVDs are the number one cause of death globally: more people die annually from CVDs than from any other cause.
- An estimated 17.3 million people died from CVDs in 2008, representing 30% of all global deaths. Of these deaths, an estimated 7.3 million were due to coronary heart disease and 6.2 million were due to stroke.
- Low- and middle-income countries are disproportionally affected: over 80% of CVD deaths take place in low- and middle-income countries and occur almost equally in men and women.
- By 2030, almost 23.6 million people will die from CVDs, mainly from heart disease and stroke. These are projected to remain the single leading causes of death.
Role of lipid and lipoprotein profiles in risk assessment and therapy. Ballantyne CM, Hoogeveen RC. Am Heart J. 2003 Aug;146(2):227-33.
Despite a strong and consistent association within populations, elevated TC [(total cholesterol)] alone is not a useful test to discriminate between individuals who will have CHD [(coronary heart disease)] events and those who will not.
3 Evidence type: observational
Relation of serum lipoprotein cholesterol levels to presence and severity of angiographic coronary artery disease. Philip A. Romm, MD, Curtis E. Green, MD, Kathleen Reagan, MD, Charles E. Rackley, MD. The American Journal of Cardiology Volume 67, Issue 6, 1 March 1991, Pages 479–483
Most CAD [(coronary artery disease)] o