Steak good. Chocolate bad?
Say it ain’t so!
Scientific American recently did a “Meta-Analysis” on scientific studies done over the last 10-20 years, on the effects of Saturated Fats and Carbohydrates on weight and cardiac risk. Meta-Analysis is a useful tool, but does not replace actual scientific studies and inquiry. A Meta-Analysis looks at all the data from multiple different studies and tries to add them all together, to sort of create a single “Mega-Study” using huge numbers of patients in multiple studies in widespread areas; studies done by a variety of groups, and with a variety of participants. This sounds GREAT in theory, but ends up being trickier than it sounds since the study parameters are all different and hard to compare. It’s often trying to make apples look like oranges, where the apple is fresh off the tree and the orange is rotten on the ground under a tree somewhere in south Florida. Sometimes the data just doesn’t mix. In this case though, it allowed the researchers to look at 350,000 study participants over 23 years of observation. Very powerful.
So what did this study show?
I’m glad I asked!
The study, which can be found here, makes some discoveries which have been hinted at for the last 10 years in the studies we read as doctors.
Saturated Fats may not be as bad for us as we thought and refined simple carbohydrates may be much worse for us than any kind of fat.
So yes, the steak you are eating may not be nearly as bad for you as we thought. It seems that while these saturated fats (long considered the “True Dietary Evil”) do raise LDL cholesterol (the bad icky stuff which clogs up your blood vessels), it also creates more of the HDL cholesterol (the “good” cholesterol which helps to transport the bad cholesterol out of your body). On the other hand, the data on refined carbohydrates looks really bad.
People with diets rich in refined carbohydrates (i.e. sugars and simple carbs) had a tremendously higher average body weight, much higher rates of Type 2 Diabetes and were almost twice as likely to get coronary heart disease.
So will the 2010 Federal Dietary Guidelines be altered to accommodate the new data? They are busily deciding that right now. Quoted from the article, a quote from Robert Post, deputy director of the U.S. Department of Agriculture’s Center for Nutrition Policy and Promotion:
Right now, Post explains, the agency’s main message to Americans is to limit overall calorie intake, irrespective of the source. “We’re finding that messages to consumers need to be short and simple and to the point,” he says. Another issue facing regulatory agencies, notes Harvard’s Stampfer, is that “the sugared beverage industry is lobbying very hard and trying to cast doubt on all these studies.”
So what is the take home message?
A balanced diet is always best, everything in moderation, but when making food choices, it may be prudent to replace highly refined carbohydrate foods with foods which consist of more complex carbs (i.e. Whole grains). Certainly, pure carbs should be avoided, or ingested in moderation (i.e. sugared sodas, candy, potato chips). I am a sugared soda drinker myself, though I have usually limited my intake to 2 such drinks daily. I will be taking steps to limit them further from my diet.
It may also be less important to remove all saturated fats from our diet, as they may end up being neutral, in a cardiovascular sense, or at least not nearly as evil as we have made them out to be.
From → Medical Topics