High MUFA Diets are (Heart-)Healthy and Probably Superior to High PUFA Diets

Ever since the "Mediterranean Diet" was/is the talk of the town, more and more people become aware of the potential benefits of the formerly largely ignored mono-unsaturated fatty acids (MUFAs). In spite of that, the majority of consumers (probably due to the misinformation coming from the marketing machinery of the food industry) still focuses on avoiding the "bad" saturated fats and consuming as much "healthy" polyunsaturated fats (PUFAs) as possible in order not to fall victim to an obesity epidemic which is inseparably intertwined with these kind of black-and-white approaches to nutrition.

In an extensive review (Jones. 2011) scientists from the Department of Human Nutritional Sciences at the Richardson Centre for Functional Foods and Nutraceuticals (University of Manitoba, Canada) evaluated data from over 50 years of research to come to the conclusion:

Consumption of dietary MUFA promotes healthy blood lipid profiles, mediates blood pressure, improves insulin sensitivity and regulates glucose levels. Moreover, provocative newer data suggest a role for preferential oxidation and metabolism of dietary MUFA, influencing body composition and ameliorating the risk of obesity. Mounting epidemiological and human clinical trial data continue to demonstrate the cardioprotective activity of the MUFA content of dietary fat.

In fact, they found MUFA rich diets to be superior even to diets enriched in PUFAs, which have lately oftentimes been hailed as the saviors of the fat and unhealthy:

When PUFA and MUFA rich diets were compared for replacement of dietary SFA in healthy adult subjects, those consuming MUFA rich diets demonstrated a preservation of HDL-C levels to a greater extent with only a 4% decrease in HDL-C levels compared to those consuming PUFA rich diets, which decreased HDL-C levels by 14%.

What is interesting, however, is that there still seems to be an initial bias against saturated fatty acids. This can also be seen from the fact that the general questions the authors pose throughout their review always come back to the idea of replacing saturated fatty acids by either carbs or MUFA, PUFA or MUFA etc. I would be interested to see a study or a review without this initial bias against saturated fats - the results could be very interesting... what do you think?

Pot Belly and High Triglycerides Indicative of Low LDL & HDL Particle Size

A recent study by scientists from the Mayo Clinic in Minnesota (Irving. 2011) found that the most reliable indicators of LDL & HDL particle size in 84 healthy non-diabetic men and women were a huge amount of trunk fat and high triglyceride levels.

[...] the accumulation of atherogenic lipoprotein particles (e.g. small, dense, low-density lipoprotein particles and small, high-density lipoprotein particles) was associated with low levels of insulin sensitivity, cardiorespiratory fitness, and higher levels of adiposity. However, multivariate forward-stepwise regression revealed that triglycerides, followed by truncal fat mass, were the strongest predictors of the lipoprotein particle size and concentration data.

These results are of particular interest to those who cannot afford having a comprehensive lipid panel done. Since the standard tests often do not provide any information about the size of the cholesterol particles, looking and triglycerides and truncal fat may be a useful indicator of whether or not it will be necessary to check cholesterol particle sizes, as well.

On a side note: Other than it has long been thought, current research suggests that neither the amount of total cholesterol, nor the amount of LDL cholesterol, but rather the size of the cholesterol lipo-proteins is the main determinant of how likely one is to develop arteriosclerosis: Large particle size = benign; small particle size = dangerous.

1.200 IU Vitamin D Won't Raise 25OH-D Levels Enough to See Beneficial Effects on Markers of Cardiovascular Health

In the course of the last weeks, I have refrained from posting each of the 1001 studies on vitamin D that appear in the myriad of medical magazines each month. It is simply too much, mostly very irrelevant information. A recent study by Maki et al. (Maki. 2011) is yet interesting insofar, as it provides some insight into the amounts of supplemental vitamin D one would probably need to see some cardiovascular benefits.

After supplementing the diets of their subjects with either a standard multi-vitamin or the multi-vitamin + 1,200IU of vitamin D for 8 weeks, the researcers measured serum 25-hydroxyvitamin D [25(OH)D] and high-density lipoprotein cholesterol (HDL-C) in subjects with high waist circumference and found:

There was a significant difference in mean change for 25(OH)D between the MVM and MVM+D treatment groups ( − 1.2 ± 2.5 nmol/l vs. 11.7 ± 3.0 nmol/l, respectively; P = 0.003). Vitamin D 1,200 IU/day did not increase 25(OH)D to a desirable level ( ≥ 75 nmol/l) in 61% of participants. There were no significant changes in cardiovascular disease risk markers. 

This is quite interesting, because even after all the fuss about vitamin D defiency that has even reached the mass media in the course of the last months, the general recommendation is not to take more than 1.000IU of vitamin D (sometimes even less) per day. For most people, this study seems to indicate, this is far too little to even get their vitamin D levels into the desirable ranges. Whether or not this would provide them with the beneficial results many scientists hope for, remains to be elucidated, though.

Overweight Boys More at Risk of Obesity Related Health Problems than Girls

In a recent study from Egypt, Hassan et.al. took anthropometric measures of adiposity from 150 pupils between the ages of 7 to 18. Along with data on body composition and serum total lipids profiles the scientists intended to find correlation between obesity and adverse health effects at younger age. The results are interesting in that no correlation was found between lipid profile and body composition in the adolescent group (12-18 years). On the other hand, in the younger children , ...

For young age [7-11 years], triglycerides and HDL-C are correlated to most of the body composition and anthropometric parameters in boys and not in girls.

The scientists speculate on whether the different fat distribution pattern in young boys (centrally dominant) could be one of the underlying reasons for this observation. Be that as it may, I consider this another good reason to encourage boys (and girls, alike) to act out their natural desire to move and exercise before they  become PlayStation cambling couch potatoes.