Although most nutritional authorities are now admitting that reducing saturated fat consumption by substituting carbohydrates was really bad advice, they, for the most part, are still sticking to the overall concept of limiting all saturated fats to <10% of daily calories and substituting “healthy” polyunsaturated fats for “unhealthy” saturated fats whenever possible.
The recently published (and highly criticized) Dietary Guidelines For Americans state:
The recommendation to limit intake of calories from saturated fats to less than 10 percent per day is a target based on evidence that replacing saturated fats with unsaturated fats is associated with reduced risk of cardiovascular disease. The limit on calories from saturated fats is not a UL set by the IOM. For most calorie levels, there are not enough calories available after meeting food group needs to consume 10 percent of calories from added sugars and 10 percent of calories from saturated fats and still stay within calorie limits.
Recommendations to limit saturated fatty acids (SFAs) to <10% of calories persist, despite a spate of recent meta-analyses showing no relationship between saturated fat consumption and coronary heart disease (CHD, also known as ischemic heart disease (IHD)).
In addition, it should be abundantly clear by now that not all SFAs behave the same with respect to our lipids or our IHD risk.
Wide Variety Of Saturated Fats
Most SFAs come from animal origins, including meat and dairy products. The types of SFAs differ markedly between meat and dairy products; the associated nutrients and their interaction with SFAs also differs widely and all of this is likely to affect the risk of IHD.
There is quite a bit of evidence that dairy fat actually lowers the risk of IHD.
For example, in the MESA (Multi-Ethnic Study of Atherosclerosis) study, each 5-g/d intake of dairy SFAs was associated with a 16% lower risk of IHD, whereas each 5-g/d intake of meat SFAs was related to a 29% higher risk of IHD.
Despite this, current guidelines continue to repeat the unsubstantiated recommendation to consume low fat dairy over full fat dairy.
Lower Risk Of Heart Disease With Dairy Saturated Fats
Hopefully, a paper just published in the American Journal of Nutrition, will provide the nail in the coffin of the concept that all saturated fats are similar in their affects on blood lipids and cardiovascular risk and should be restricted.
This study found that higher intakes of SFA in 35,597 Dutch men and women were associated with lower risks of ischemic heart disease (IHD).
In other words, the more SFA the Dutch eat, the less their chance of having a heart attack.
And, the association “did not depend on the substituting macronutrient.” Those who ate less saturated fats and more “healthy” polyunsaturated fats did no better than those who substituted carbohydrates.
The association was dependent “on the chain length and food source of SFAs.”
The authors noted that the lower risk of IHD was driven by consumption of:
short-to-medium chain SFAs (myristic acid, the sum of pentadeclyic and margaric acids, and SFAs from dairy sources including butter, cheese, and milk and milk products.
Skeptics amongst my readers might think that this study was funded by the dairy industry, but as Marion Nestle pointed out on her Food Politics blog, support came from Unilever, who would have a vested interest in promoting their low saturated fat/high polyunsaturated fat margarines as substitutes for butter fat. This is only one of 11 industry-funded studies with findings different from what the sponsors would have liked, versus 105 studies with findings supporting products of the sponsors (since Marion has been tracking such studies).
It’s likely that some saturated fats, especially when eaten immoderately, without an otherwise balanced and diverse diet, can increase your risk of heart disease.
However, the saturated fats that come from dairy products are clearly not contributing to heart disease risk or obesity and our nutritional guidelines should recommend full fat dairy, not low fat or non fat products that require addition of added sugar to maintain palatability.