Question: “Per the debate over carbohydrate intake, what is the overall volume/ratio in your diet in relation to weight gain and particularly to that number one question you hear people ask about whether they’ll get fat eating carbs for dinner?” – Anonymous
Short Answer: Calories in excess cause weight gain, not carbohydrates. When calories are consumed in excess of the body’s needs, the body stores those calories in the form of fat tissue.
We vilified this poor macronutrient
Before I jump into the science-y stuff, I thought I’d mention that the “carbohydrate debate” is not really a debate in medical communities. Carbohydrates are the body’s preferred source of energy. Carbs are essential for the brain, immune system and red blood cells to function properly. The Dietary Reference Intakes (DRIs), established by the USDA, recommend that adults consume carbohydrate at a range between 45-65 percent of total calories per day.
It’s the “refined carbs” to be wary about
Why carbs have gotten a bum rap: the fastest way to consume calories in excess of the body’s needs is in the form of “refined carbs.” Why? Refined carbohydrates have added sugar, which is sugar listed on a nutrition label in the form of high fructose corn syrup, glucose, syrup, nectar, etc. When a product has added sugar, the total calories drastically multiply in that product.
What this means as far as weight gain
It’s easier to gain weight when the majority of your diet is full of refined carbohydrates. The Academy of Nutrition and Dietetics has not established an “RDA” or recommended daily allowance for added sugar. However, the Department of Agriculture and some non-profits (like CSPI, the Center for Science in the Public Interest – amazing organization) have recommended no more than 10 teaspoons of added sugar, which comes out to ~40 grams. Remember this is ADDED SUGAR. You would not include a banana or apple to this limit, because people did not add sugar to natural fruits.
Let’s look at this in an extreme case.
Pretend you decided to eat all of your calories for the day in the form of bread. You would feel, (a) bloated, (b) constipated, and (c) less sated due to consuming one macronutrient. But here’s the kicker: you’d maintain your weight. Maybe your weight would fluctuate by a pound or two, since glycogen (our energy storage) requires water to be stored. But the reality is that if you only ate the amount of calories you needed to maintain your weight (even if through carbs), you would maintain your weight.
Demystifying the carbohydrate conundrum
There are refined carbs (as mentioned above) and there are complex carbs (fruits, veggies, nuts, seeds, legumes, beans, starchy veggies, grains, whole wheat breads and whole wheat pastas). Here’s where percentages of carb versus protein versus fat come into play. The more nutrient dense the diet, the better off your health and your weight. Thus, having a greater percentage of carbohydrate one day over another and a drop in protein or fat (within your calorie needs) will not make you gain weight. Does this mean we always have to eat between 45-65 percent of our calories from carb? No. But it does not mean that including a carb will cause weight gain, either.
What this means as far as practicality…
Adults need at least 130 grams of carbohydrates per day, 38 grams of which should be fiber for men and 25 grams for women. 130 grams is not a lot of carbohydrates – especially for an active person. Thus, it is appropriate to assess your baseline calorie needs, followed by a measurement of your current activity factor. By doing so, you establish a range of calories you require on a daily basis. I typically like to use the Harris Benedict equation to assess kcal needs.