4 Myths About High Carbohydrate Foods That Need to be Buried
The nutrition industry is chalk full of myth and hyperbole. Why? Probably because people was notoriety and to sell books. Let’s face it, rationale, clear headed thinking doesn’t get a lot of hype and generate 6 figure book deals.
Currently there are a lot of myths floating around about high carbohydrate foods. Most of which are the result of small truths that have been twisted into big lies. It is time to recover the truth and bury some of those myths.
Myth #1: High Carbohydrate Foods Make You Fat
Carbohydrates have gotten a “bad rap” because they elicit an insulin response. And as everyone knows, insulin causes us to become fat (or does it?). Unfortunately, when we look closer at the science this idea doesn’t quite hold up.
Insulin is an endocrine hormone, meaning it affects multiple tissues in the body. Specific to our focus is muscle and fat. When skeletal muscle is “exposed” to insulin signals the muscle cell to shift to carbohydrate-based metabolism.
Interestingly, the overall energy status of the cell plays a role in exactly what happens in the muscle cell. Meaning, if the muscle cell is low on glucose and/or muscle glycogen the insulin signal will instruct the cell to utilize the incoming glucose for fuel and to begin creating muscle glycogen from any spare glucose that is coming in.
Additionally, insulin will cause an uptake of fat into the muscle. If the muscle cell is already full of glucose and glycogen and topped off with intramuscular triglycerides then insulin signaling will do all of the things it does in a low energy state but will also turn excess glucose into fat through de novo lipogenesis (a point we will get to later in the article.
Insulin also acts on our fat tissue. Insulin does in fact decrease the rate of lipolysis (fat breakdown) in adipose tissue and also it does stimulate fatty acid and triacylglycerol synthesis (fat creation). The science is crystal clear on this.
Now it would indeed appear that insulin promotes fat storage… well unfortunately that is the wrong wording for it. Insulin is “fat-sparing”, not fat promoting.
Yes, insulin does reduce fat oxidation and promote a lipogenic environment. However, for insulin to have a profound effect on body fatness and fat gain, it has to occur in the presence of excess calories.
Put simply, our bodies default metabolic state is one of fat oxidation and insulin is the switch that turns it to carbohydrate metabolism. The net effect of insulin is simply a switch in substrate metabolism, it does not produce a large “obesegenic affect” due to dietary composition alone.
We should also point to one critical piece of evidence: protein also elicits an insulin response. In fact, some high-protein foods elicit a greater insulin response than high-carbohydrate foods (has your brain exploded yet? I know mine did when I first read this article).
Why is this important? Well one of the most consistent finding from nutritional research is that diets higher in protein are effective in reducing body-fatness. So if insulin were the main culprit in body-fatness than consuming protein would also encourage fat accumulation and not fat loss.
Myth #2: Don’t Eat High Carbohydrate Foods At Breakfast
There is a lot of talk about how you should avoid high carbohydrate foods at breakfast because it elevates insulin and stops your body from burning fat. There is also a lot of discussion about how carbs at breakfast won’t make you feel full.
Well, we just killed the carb-insulin-fat hypothesis in the first myth so we should already be skeptical, but there is even more evidence that eating carbs at breakfast doesn’t make you fat and that higher-carb breakfasts can actually make your more full.
Studies in normal and obese males and females have shown that high-carb breakfasts can indeed be highly satiating and are not “fat promoting”, nor do they lead to bad regulation of blood sugar. This is also really interesting, it turns out that if you skip carbs at breakfast you are more likely to choose carbs at lunch, it is almost like your body wants some balance
Now let’s be clear, this is not to say you have to, or should, eat high carb at breakfast. It simply means that avoiding carbs at breakfast unwarranted.
Myth #3: Excess Carbohydrates Turn into Fat
We’ve all heard that when you eat more carbohydrates than you need your body turns them into fat. Well, that is technically true, but in real-world scenarios it would be pretty difficult to actually achieve this.
When you consume carbohydrates your body will store a lot of them as glycogen in your muscles and liver. Now if you consume enough to fully top of the glycogen storage most of the excess actually gets burned off, your body simply switches from fat oxidation to glucose oxidation. It is only when you consume carbohydrates above your energy need (i.e. consuming more calories than you are burning) that they are stored as fat.
Also, it looks like for the average person you can consume about 500 grams of carbs before you start turning it into fat. Now I don’t know about you, but 500 grams in a day is about my “unbutton” the pants limit. Doing this on a daily basis is probably not realistic so I wouldn’t worry about de novo lipogenesis too much.
Myth #4: Skipping Carbs (or Fasting in General) Before Training is Better for Fat Loss
Ancient fitness lore tells us that skipping pre-workout carbs/ training fasted increases your fat loss because your body will be using more fat for fuel during the workout. For decades poor souls have been enduring training sessions on an empty stomach in hopes of getting shredded.
Well, the ancient lore can go to the burial ground. It turns out training fasted is no better for fat loss than training in a fed state. In fact, it may be more beneficial to train fed!
A 2014 study by some super smart dudes (Brad Schoenfeld, Alan Aragon, and James Krieger) explicitly showed no difference in fat loss between training fasted versus training with carbs on board (and some protein and fat).
Now this is really interesting because there is a ton of research showing that consuming carbs before a workout can increase your training capacity, so it would stand to reason that if you can train harder you will get better performance and fat loss. Thus, consuming carbs before training might actually be better for fat loss in the long run.
The Wrap Up
Clearly high carbohydrate foods are not the monster that lore has portrayed them to be: they don’t make you fat, you can eat them at breakfast, a high carb meal won’t instantly turn to fat, and you can eat them before you train.