The Skinny on Fats
As I sat in the kitchen dipping my vanilla creme cookie into a glass of milk, I read the side of the Snackwell's box: 40% Less Fat, the Healthy Choice for Snacking. The dryness of the cookie necessitated milk-dipping. Before I knew it, I had consumed half of the box and 400 calories...and I was still hungry.
If you lived in the 90's, you might remember the Snackwell's craze. Fat-free and low-fat were the marketing phrases that caught the eye. Fat in food, fat on my body...it was a logical connection. Fats made you fat, so the lower the fat content in foods, the better. Little did we know.
Now, the pendulum has swung the other way: fats are good, carbs are bad! So what's the real skinny on fats? Well, like carbs, some fats are good, some fats are bad.
First, from a health and weight loss perspective, it is important to note that fats have 225% more calories per gram than carbohydrates or protein (9 calories per gram, versus 4 calories per gram for both carbs and protein). But when it comes to losing weight, the ratio of fats, carbs, and protein really doesn't matter; what matters is total caloric intake.
We do need some fat in our diets, and the type of fat is essential for health. Trans fats (fats from partially hydrogenated oil) should be avoided at all costs. Trans fats negatively affect cell function; additionally, they significantly elevate LDL cholesterol (the "bad" cholesterol). Saturated fats are ok but should comprise only 10% or less of total fat intake -- saturated fats, too, increase LDL cholesterol. Both trans fats and saturated fats have been shown to contribute to inflammation.
Polyunsaturated fats (omega-3's and omega-6's) and monounsaturated fats (olive oil) are the ideal fats for health. Both polyunsaturated fats and monounsaturated fats increase HDL cholesterol (the "good" cholesterol). Studies have shown that replacing saturated fats or refined carbohydrates with these two kinds of fats can reduce inflammation in the body and significantly decrease risk of cardiovascular disease.
This brings us back to Snackwell's: Was it a good snacking option? The problem with many low-fat foods is sugar content -- often, there is a high number of sugars or refined carbohydrates. This not only contributes to inflammation in the body, it also piles on the calories -- without that feeling of "fullness." When our bodies break down fats, our cells release a satiety hormone making us feel full. If we consume low-fat foods, we may not get the same "full" feeling that fats provide, causing us to eat more and consume more calories.
But we need to be careful to balance our pendulum. We need to eat the right fats in the right amounts. The recommended intake of dietary fat is between 20% and 35% of total calories per day. If we consume trans fat or too much saturated fat, we may find ourselves at risk for cardiovascular disease. For those of us in our 30's and 40's, that may seem like a long ways off -- but the catch is to start now. Our arteries become clogged over time, so everything we are doing now will ultimately affect our future health.
What foods provide healthy monounsaturated or polyunsaturated fats? Olive oil, sardines, salmon, albacore tuna, nuts, seeds, eggs, and avocado are all great sources. Animal products (dairy, meats) often contain high amounts of saturated fats, so just be careful (10% or less of total fat for the day). Packaged foods (like Snackwell's) sometimes contain trans fats; look for "partially hydrogenated oil" in the ingredients.
Hungry for more? Check out my blog post on eating well for life!