Just as fats used to be, carbs are now being accused of causing weight gain and heart disease, and all sorts of other health problems. But just like high-fat foods, not all high-carb foods are created equal. In fact, many of the world's healthiest foods have plenty of carbs in them. In this article, I'm looking at the top five reasons not to fear carbs, the last one we really can't argue with.

Reasons NOT To Fear Carbs

Number one, early humans ate carbs all the time.

Learning to cook was a game-changer for our early ancestors. Cooked meat provided increased protein, fat and calories. But a flurry of new evidence indicates that carb-rich foods like root vegetables, legumes and even grains were cooked and consumed by our early ancestors as well. Now this is important since cooking these foods makes many of them safer to eat, particularly legumes. Now, not only would cooked carbs have been more nutritious, they may have also been more appealing to a hungry hunter-gatherer. This theory is supported by emerging biological evidence that shows early humans began developing extra copies of the amalyase gene, which helps produce the enzymes you need to digest starchy carbs. By analyzing bone DNA, researchers can see that early humans in Europe had developed extra copies of the amylase gene long before they started farming.

Number two, carbs are not inherently fattening.

Okay, hear me out here because many people misunderstand what this statement actually means. It's true that low-carb diets can be incredibly beneficial, especially for things like weight loss or diabetes and some other health conditions and at Authority Nutrition we talk about a lot. But that's because low-carb diets are high in protein which has its own positive effects on metabolic rate and suppressing appetite, and low-carb diets are also lower in refined carbs in junk food that are bad for health. So overall, this makes it lower in total calories than the typical Western diet. It's not because carbs are fattening themselves. Some sources claim that carbs are the primary cause of obesity due to their effects on insulin and fat storage. In other words, that carbs are uniquely fattening, regardless of total calories. Now this is called the carbohydrate-insulin hypothesis. The truth is, scientific evidence overwhelmingly rejects this hypothesis. The latest was a metabolic ward trial that compared a high-carb diet, which was 50% carbs, and a very low-carb ketogenic diet, which was 5% carbs for four weeks at a time. The diets were equal in calories and protein and subjects had no access to any outside foods for the entire time. After the first four weeks on the high-carb diet, participants lost 1.1 pounds, or half a kilo of body fat on average. This is shown by the blue line in Dr. Guyenet's graph which doesn't show the first two weeks of the high-carb diet because the first body composition measurements were at the two-week mark. But then, after switching to the very low-carb diet for the remaining 30 days, from day zero on this graph, participants lost just 1.1 pounds of body fat again. Now, this is was despite a sharp drop in insulin levels by almost half in that 30 days. So there was no difference between the eating patterns and fat loss despite the huge difference in insulin. Effectively disproving the carbohydrate-insulin hypothesis. Even if we ignore the clinical studies, which is the powerful evidence we have, the idea that carbs are inherently fattening doesn't fit the historical and observational evidence available. Indigenous groups like the Tarahumara Indians and Kitavans all thrived on high-carb diets for hundreds of years. Obesity was rare if not non-existent in all of these indigenous groups. For example, Kitavans have virtually no overweight people and very low insulin levels, despite a diet that was 70% carbohydrate. So immediately there we can see that carbs, albeit they are healthy carb sources, but they're still carbs, they're not making them fat. The same was observed for pre-industrialized Asian populations up until the 20th century. They were living on staple foods like rice, noodles, potatoes, and fruit. Even by the 1990s, 50 to 60% of calories eaten in Japan and China still came from carbs. And this was more than the US or UK, yet obesity rates were much, much lower. If carbs themselves are fattening, these populations would not have had lean bodies and good health overall, regardless of how active they were.

Number three, fiber is important for optimal health

and it's a carbohydrate. Nutrition is rarely black and white, but one thing that all the experts agree upon

is that more fiber is beneficial for health. Soluble fiber in particular is known to be good for heart health and weight management. It's a type of carb found in high-carb foods like legumes, potatoes and oats. It helps to increase the time it takes to digest and absorb nutrients. This leads to a longer feeling of fullness and a significantly reduced appetite. It's also closely linked with important fat loss around the heart and other organs, it's known as visceral fat.

Number four, gut bacteria rely on soluble fiber for energy.

The role that the bacteria in our gut may have on health is a really new and exciting area of science. It's thought that the balance of good and bad bacteria in our gut can really influence our risk of developing lifestyle diseases, ranging from physical to psychological. In order to grow, the so-called good bacteria need carbs that they can ferment for energy. As it turns out, soluble fiber appears to be the important gut-nourishing nutrient that they feed on. Now once again, some of the absolute best food sources of soluble fiber include legumes and oats, which are high-carb foods.

Number five, the world's longest lived

populations eat plenty of carbs. The regions where people live measurably longer lives, also known as blue zones, provide us with unique insights about certain eating patterns. The island of Okinawa in Japan has the most centenarians, or people who live over the age of 100 in the world. Their diet is very high in sweet potatoes, green vegetables and legumes. In fact, a massive 85% of an Okinawan's caloric intake came from carbs prior to the 1950s, 85%. Now more than 65 years later and so many of them are still alive and well. Those from the Greek island of Ikaria also live long and healthy lives. Almost one in three inhabitants lives to be 90 years old, which is two and half times the rate of Americans and they are also known to have a high-carb diet with lots of breads, potatoes and legumes.

So as you can see, it's really important to think of foods as a whole not just by individual nutrients and this is especially important when we're talking about carbohydrates. Carb-laden junk foods are completely different to natural whole foods that happen to be high in carbs. I guess the punch line is some do very well eating little carbs while others function perfect fine eating a lot of nutritious, high-carb foods. Different strokes for different folks.