How many of you buy low-fat foods? If you do, why? Do you even know, or is it just one of those subliminal messages that everyone seems to hear and heed? Since 1977, it has been a government recommendation to limit our fat intake to no more than 30% of our daily calorie intake. The current guidelines still put a strong emphasis on reducing fat in the diet, especially saturated fat, and cholesterol.

I used to eat low and non-fat foods. I used to think they were healthier than their full-fat counterparts (well, they do have less calories). But remember that little talk we had about the quality and the quantity mattering? Keep that in mind, will you?

In my last year of undergrad at Virginia Tech I had to do a semester-long research project on a topic of my choice. I chose to study how cholesterol levels in the body are affected by dietary fat intake. What I found was quite interesting and has now come out in mainstream media. Here is an excerpt from an article published in the American Journal of Clinical Nutrition:

The approach of many mainstream investigators in studying the effect of consuming saturated fats has been narrowly focused to produce and evaluate evidence in support of the hypothesis that dietary saturated fat elevates LDL cholesterol and thus the risk of CAD. The evidence is not strong, and, overall, dietary intervention by lowering saturated fat intake does not lower the incidence of nonfatal CAD; nor does such dietary intervention lower coronary disease or total mortality.

The major point: eating fat (including saturated fat) does NOT have an adverse effect on cholesterol levels in the body, nor does it increase the risk of heart disease. Sounds backwards, right? I know! It just goes to show that we have to constantly be open to change and educate ourselves based on new research. If you want to read more about the science behind my conclusions, check out this article and the studies that it links to.

The other thing I have learned is that fat doesn't make you fat, but sugar (and carbohydrates in general) may! Here is another excerpt from the aforementioned article:

To assist the public in following the guidelines for a lower intake of dietary fats, the food industry reformulated commodities and processed foods. Despite these changes in the food supply, the results of the National Health and Nutrition Examination Survey data-collection studies in the US indicate that the replacement of dietary fat with dietary carbohydrate failed to reverse the trend of an increasing incidence of obesity in the population. Although a reduction in dietary fat is logically matched to increased dietary carbohydrate, the role of carbohydrates in weight gain is unclear. However, carbohydrates increase blood glucose concentrations, which stimulates insulin release, which in turn promotes the growth of fat tissue that can cause weight gain. Increased obesity is associated with the metabolic syndrome and hypertriacylglycerolemia, a recognized atherogenic risk.

So we have replaced fat intake with carbohydrate intake, but we are still seeing rises in heart disease, high cholesterol levels, obesity, metabolic syndrome, etc. Hmmmm...

I love this article by National Geographic that shares the story of how sugar came to be abundant in our lives and why that's such a bad thing.

That brings me back to quality versus quantity. If you look at most low-fat foods in comparison to their full-fat counterparts, you will notice two things:

They are a bit lower in calories.
The fat that was removed was replaced by sugar or artificial sweetener (they usually have to sweeten the low-fat foods to make them palatable).

When you replace fat with sugar, the food becomes less satiating. That means that instead of feeling satisfied after just one serving, you will want to reach for a second in order to feel full. Having that second serving and feeling full results in more calories consumed than if you had eaten just one serving of the full-fat food. Plus, it's going to spike your blood sugar levels and then you will feel a crash in energy once the sugar is cleared from your blood stream.

Am I saying that everyone should follow a high fat, low carb diet? No. I truly believe in moderation in all things. Just promise me that you will think about why you are reaching for the box labeled "low-fat" and compare its nutrition label to the full-fat version next time. Fat is not our enemy. Choose the satisfying calories over the empty ones, even if that means that you have to consume a slightly larger quantity of them.