What’s a better snack/meal – one that is low in fat, and high in carbs, or one that is low in carbs, high in fat? Or maybe it’s a snack that’s low carb, low fat, gluten-free, dairy-free, and organic.
Original source: here.
That’s what we’ll cover today.
But before we get there, let’s give some definitions, so we’re all on the same page. What exactly makes a snack/meal high in fat, and low in carbs (we’ll call this “HFLC” from now on)? If more calories come from fat than from carbs. And I do emphasize calories – not grams. The reason is that you might look at a label, and it shows for example that something has 10 grams of fat, and 18 grams of carbs. So you’re thinking it’s a “LFHC” meal. But you’d be wrong. The reason for that is one gram of fat contains 9 calories. One gram of carbs contains 4 calories. So something with 10 grams of fat has 90 calories, and something with 18 crams of carbs has 72 calories.
The opposite is true as well. A meal that is high in carbs and low in fat (we’ll call this “HCLF”) will have more calories from carbs than from fat.
With those definitions out of the way, let’s see the impact of different snacks.
Your Weight and Your Body Fat
Assuming that all the other variables are constant – protein content and total calories – there will be no difference to your weight regardless of whether you choose a LFHC snack, or a LCHF snack. Study after study examining whether changing the composition of a diet from LFHC to LCHF makes a difference (assuming calories and protein are equal between groups) to overall weight. The conclusive answer is: no.
OK, so there’s no differences in weight. But you’re a smart reader – after all, you’re reading my article. You know that it’s not about weight. It’s about fat. Does the composition of the diet affect fat loss, instead of weight loss? The answer again is: no.
So in the strict academic sense, there’s no difference between LFHC or LCHF in terms of body composition, or total weight. But we don’t live in a strict academic world, and there’s something called “real life.” In real life, most snacks that are low in fat also happen to be high in protein.
Original source: here.
And protein makes a big difference. In multiple studies when calories between diets/snacks are equally matched, but one group has a higher protein content, that group loses more weight and fat. The reason for that is something called the “thermic effect of food.” What that means is that whenever you eat a food, you don’t absorb 100% of those calories. Some of those calories are used to help you digest and assimilate the food you just ate. With fat, it’s about 2-3%. With carbs, it’s about 5-10%, and with protein, it’s about 25-30%. So if you eat 100 calories of pure fat, you’ll absorb 97-98 of those calories. With carbs, you’ll absorb 90-95, and with protein, you’ll only absorb 70-75.
The other issue to consider is that protein tends to be more filling than carbs or fats. So that gives us a double whammy – first, it helps you burn more fat. Second, you eat less because it’s more filling.
So although the quantity of fat lost on a LFHC vs. LCHF diet is virtually identically, the location may be different. According to multiple studies, with low carb diets, fat is preferentially recruited from “stubborn” areas. Lower body for women, belly for men. This was written about in more detail in Lyle McDonald’s excellent book, The Stubborn Fat Solution.
Insulin and Diet Composition
So besides weight and body composition, are there any other notable effects of diet composition on anything? The answer is yes – your insulin. There is no question that lower carbohydrate diets result in lower insulin levels compared to lower fat diets, according to multiple studies. So even when calories and protein are equal, lower carb diets result in lower insulin levels, compared to lower fat diets.
If you’re at risk for diabetes, or you already have it, a lower-carb snack may be better than a higher carb snack of equal calories. If you’re not at risk for diabetes, there’s not much of a difference.