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Will Carbs Make You Fat?


Almost everything you see here is a carb! Minus the meat and oil.
by Kim Schlag
What Even Are Carbs?
If you go based on headlines you might think carbs are the superillain in the latest Marvel movie.

The real answer is far less exciting.

​Carbohydrates are one of three macronutrients that make up our food (protein and fat are the other two.)
Carbs are categorized by how simple or complex their chemical structure is.  I’d list those categories and the various carbs in each, but I actually want you to read this article while awake.

Just know this: In the end, most carbs are digested into the sugar glucose before they’re absorbed into the body.  So whether you eat oatmeal or poured a few teaspoons of sugar into your coffee, they’ll both end up as glucose.

Carbs are your bodies main source of energy.  Interestingly, if you don’t eat carbs your body will use fats and protein for energy. So while you can’t survive without protein and fat you can survive without carbs.

Just because you can survive without them though doesn’t mean you should, or that it’s better. Carbs provide much in the way of micronutrients and fiber.  Yay for health & pooping!

Also, if you like lifting heavy things or running really far, or generally sportsing hard you should know that carbs can help optimize your performance in all of your hard sportsing.  

Besides, I think that we can all agree with Oprah…

Which foods contain carbs?

  • Grains: bread, pasta, rice, cereal, crackers, pretzels
  • Potatoes
  • Vegetables
  • Fruit
  • Dairy
  • Sweets

Surprised by any of those? 

Why are people afraid of carbs?
Can’t say for sure but some good possibilities include:

  • Nutritional science is still young. We’re learning as we go. 
  • The media loves a good story. “Everything works.” doesn’t attract a lot of viewers/readers, but “____ food will make you fat/ burn fat/ cure cancer etc? That stuff’s good for business. 
  • The words insulin & sugar  

So, do carbs make you fat?
Short answer? 
Longer answer:
There is a growing body of scientific evidence, including a large randomized clinical trial published just last year, that shows that when protein and calories are matched there are not significant differences in weight loss between low-carb and low-fat diets. The same study also found no association between insulin production and weight loss.

I’m not sure how interested you are in reading actual studies but I’m going to link them below in case you are:) In any case, here’s the take home point: Both low carb and low fat diets work for weight loss, so choose what you can stick with, remembering the critical point is total calories. 

But what about eating carbs at night? 
It still comes down to total calories.  If eating carbs at night (or protein or fat for that matter) means you eat more calories than you burn in a day than, yes, you’ll gain weight.  But the same would hold true whether those calories were eaten at night or not. If you eat more calories than you burn, even if you eat them earlier in the day it will have the same effect.

But I have to eat carbs low on the Glycemic Index, right?
So the GI is a ranking of carbohydrates according to how fast they cause your blood sugar to rise. The higher the ranking on the scale from 1-100, the faster the food causes your blood sugar to rise. The idea many people have is that for fat loss low GI carbs are best.

Let’s talk common sense first.  If you look at the index you’ll find that watermelon is ranked a 77 while Peanut M&M’s are ranked a 33. Now in my fantasy world Peanut M&M’s are a supreme fat loss food, but realistically speaking does it seem logical that you should consider Peanut M&M’s part of a fat loss diet but shun watermelon?

One of the major problems with the GI is that it looks at food in isolation, yet that’s rarely how we eat food.  When’s the last time you sat down and just ate rice for lunch? 

As to the science, in studies that control for macronutrients and fiber there is no fat loss advantage to the low GI diet vs the high-GI diet.

What should you focus on when it comes to carbs and fat loss?
First do this:

  • Keep total calories in check by eating fewer calories than you need to maintain your current weight.
  • Eat adequate protein: 0.7 to 1.0 gram per pound of your lean body mass (use your goal weight for LBM)

Then, as far as carbs:

  • The remainder of your calories can be divided between fats and carbs however you prefer.
  • The majority of those carbs (80-90%) should come from whole, minimally refined, nutrient dense sources​.

That’s really it. 
Don’t overthink this.
Carbs aren’t the villain.
​They’re also not the sexy super hero played by one of the Hemsworth brothers either.  

Yes, I mostly wrote that to have a reason to share this fine picture. But seriously, its food not a summer blockbuster. We can cut way back on the drama. If you start to feel worked up about it remind yourself that food doesn’t have moral value.  It’s just food.

Email me any time if you have questions about how to put any of this into practice:) 

Gardener et al: Effect of Low-fat vs Low- CarbohydrateDiet on 12 -Month Weight Lossin Overweight Adults and the Association with Genptype Pattern or Insulin Secretio. JAMA 2018
Karl, JP et al. effects of Carbohydrate quantity and Glycemic Index on Resting Metabolic Rate and and Body Composition During Weight Loss. Obesity. 2015