Carbohydrates are the current culprit for obesity. Back when the conventional wisdom dictated that fat, especially saturated fat, was bad for you, many food companies started to extensively promote low-fat foods such as pasta, cereal, crackers, chips and even pastries as the “healthy” alternatives to foods such as meat and dairy products. Because people were afraid of butter and cream, food companies avoided those ingredients. What did they add back in to keep their food products interesting? Usually it was sugar and white flour, both low in fat but high in carbohydrates. But even though they avoided fat, Americans didn’t get any thinner.
One of the lone voices dissenting from the low-fat philosophy was Dr. Atkins, whose “Atkins diet” claimed that it was carbs, not fat, that made you fat. A few years ago, the Atkins theory, which was backed up by other low-carb diets like the South Beach diet, really caught on, such that carbohydrates are currently thought to be as bad as fat once was. Some alternative nutritionists now argue that we weren’t even meant to eat starchy carbohydrate foods at all but should stick to our primal, hunter-gatherer origins and eat meat, berries and roots. What has been the result of all this theorizing? Food companies have jumped on the low-carb craze and come out with lots of low-carb foods, just like they did, and are still doing, with the low-fat craze.
As always, the goal of food companies (sometimes working in tandem with nutritionists and diet-book authors) is to convince you that you can only eat certain foods – that is, the ones that they produce and sell – and then get you to buy them. They argue that the foods made naturally – whether it’s butter, or bread made from whole wheat – are not good enough, and need to be refined and then enriched or replaced entirely with artificial creations. In my opinion, however, there is nothing wrong with natural sources of fat or carbs; in fact, some of the healthiest foods are high-fat and high-carb foods. In the last article, we talked about natural, healthy sources of fat and how to include them in your diet. In this article, we’ll talk about healthy, natural carbohydrates and how to get enough of them to stay full and satisfied without gaining weight.
What are carbohydrates?
Carbohydrates are molecules made up of the atoms carbon, hydrogen and oxygen. Much of the food we eat consists of carbohydrates. Grains, including wheat, rice, corn, millet, buckwheat, barley and oats, are the most well known high-carbohydrate foods. However, fruits and vegetables are also made up mostly of carbohydrates, as are beans. In fact, one of the most ubiquitous carbohydrate foods, sugar, is derived from fruits and vegetables. Not all of these carbohydrate foods are identical, though; there are three distinct kinds. The first group of carbohydrates is sugars. Foods that are mostly made up of sugars include fruit, sweet vegetables, and the pure sugars derived from them, such as maple syrup, corn syrup, and cane sugar. The second group of carbohydrates is made up of starches. Whole grains, bread, beans, and potatoes are foods that are mostly starch. The third group of carbohydrates consists of foods that are mostly fiber, like green leafy vegetables. None of these foods are 100% sugar, starch, or fiber. However, it is possible to process foods down to that point. White sugar, also known as sucrose, is indeed pure sugar. It comes from sugarcane or from beets, which, while they contain sugar, also have some fiber and starch. You can also get fiber supplements at the store, but a high-fiber food, like collard greens, also has a little sugar and some starch in it, particularly in the stem. So don’t make the error of thinking of a food as a “sugar” or a “starch”; most foods have some of each kind of carbohydrate.
The difference between these three groups is really only one of degree. Sugars, which include glucose (the kind of sugar in our blood), fructose (the kind of sugar that is in fruit), and sucrose (the aforementioned white sugar) are the simplest forms of carbohydrates. They are also known as monosaccharides and disaccharides. Monosaccharides can be absorbed into the blood without any metabolism necessary. Disaccharides have to be broken down into monosaccharides to be absorbed, but their metabolism is extremely quick. The more simple sugars a food contains, the more quickly we digest it and absorb it into our blood.
Starches are made up of long chains of glucose saccharides. For this reason the digestive system needs more time to metabolize them and absorb them into the blood. Starches, again, come from plant foods like grains, beans, squash and potatoes. These “complex carbohydrates,” also known as polysaccharides, are created by plants as a way of storing glucose energy. Enzymes in the human digestive system break them down into disaccharides and then into monosaccharides.
The final category of carbohydrates, fiber, is also a polysaccharide, but so complex that it cannot be broken down by the human body. There are two kinds of fiber. Insoluble fiber passes directly through the intestines without being absorbed. Because it attracts water, it softens the stool, making bowel movements easier. The other kind of fiber, soluble fiber, ferments inside the large intestine and yields beneficial short-chain fatty acids. Most plant foods contain both soluble and insoluble fiber; beans, grains, fruits and vegetables all provide us with abundant fiber.
What are carbohydrates good for?
Because carbohydrates are easy for the body to metabolize and quickly absorb into the blood, they are an excellent source of energy (calories). Carbohydrates are to our body almost like gasoline is to a car. Following the development of agriculture and the subsequent growth of human populations, most people have depended on high-carbohydrate plant foods to get them through a physically intense workday. Since meat was traditionally not widely available, most people around the world for thousands of years depended on a combination of grains, beans and starchy vegetables like yams and potatoes to provide most of their sustenance, and ate highly prized meat and fat when they could get it.
What happens when we don’t eat carbohydrates? The body still needs energy from glucose to function properly. If it doesn’t have carbohydrates (the most efficient source of glucose), it will burn fat for energy. It will even break down muscle tissue and draw on protein stores if desperate. This process is known as ketosis. It’s a way for us to survive even in periods of famine. Many low-carbohydrate diets make use of ketosis as a way to help people lose weight. In my opinion, though, starvation is not the best way for people to lose weight; a moderate diet with the right kind of carbohydrates is a much more sensible option.
Carbohydrates are not just important for providing us with energy to undergo physical activity. Glucose is also the fuel that the brain needs to function. If you starve yourself of carbohydrates, you can slow down your brain’s ability to function properly and lose your ability to think clearly.
In sum, sugars and starches are important for keeping both your body and mind running. Fiber helps you to digest your food more easily and provides us with short-chain fatty acids that contribute to a number of important physical processes. Including some of all these kinds of carbohydrates in your diet is very important.
What kind of carbohydrates should I eat?
Many people are now cautious about carbohydrates because they’re linked to weight gain. I grew up on a high-carbohydrate diet: the Macrobiotic diet. The diet is mostly whole grains, with a ton of vegetables, some fruit, and occasionally beans. Fat hardly ever puts in an appearance (except for a little sesame oil here and there), and protein is pretty low (you get some protein from combining grains and beans, but high-protein animal products are out). Everyone who goes on this high-carbohydrate diet loses weight like crazy, no matter how much food they eat (and sometimes it’s a lot, because the diet is not very filling).
Why didn’t macrobiotic people get fat on carbohydrates? It’s because not all high-carbohydrate foods are alike. There are two kinds: carbohydrate foods that occur in nature, which contain not just carbohydrates but also vitamins and minerals; and carbohydrate foods that have been processed to the point where they are just pure sugar or starch. To understand what the difference means for your body, we’ll have to talk a little more about food chemistry and what happens when you digest carbohydrates.
Carbohydrates start being metabolized in the mouth, when acted on by the salivary enzyme amylase. They are broken down into their simplest form, that of glucose monosaccharides, in the small intestine. Glucose molecules are small enough to be absorbed through the intestine into the blood, where they can be used for energy (a process called catabolism).
When we eat a natural, whole form of a carbohydrate food, such as brown rice, quinoa, black beans, carrots, onions, apples, bananas, etc., we digest not just pure carbohydrates, but also other compounds such as vitamins, minerals, other nutrients, and water. Natural foods like grains, fruits and vegetables are constituted such that all of their components combine for gentle and steady digestion, which results in a gradual, consistent flow of glucose into the blood and therefore a calm, steady energy level.
What kind of carbohydrates should I avoid?
Unfortunately, many people don’t get their carbohydrates from whole, natural foods, but rather from refined, processed foods. The two kinds of carbohydrates that are in most processed foods are sugar, or high fructose corn syrup, and white flour. These two foods are pure sugar and pure starch, respectively. They constitute most cereals, breads, pastas, chips, candies, bagels, pastries and crackers. What happens when we eat these foods? Because they contain pure carbohydrates and little else, they are digested very rapidly. This means that our blood gets a flood of glucose all at once. Having high blood sugar levels gives us a lot of energy, but it’s dangerous for your body’s health. To keep blood sugar within safe levels, the pancreas secrete the hormone insulin, which stores glucose in the cells in the form of glycogen (a polysaccharide) and in the form of triglycerides (fatty acids). Responding to dangerously high blood sugar levels, the body overreacts and takes too much sugar out of the blood, leaving us fatigued and irritable. At this point we often reach for more pure sugar and white flour-containing foods, and the cycle begins again. If this happens too often, a person’s insulin production can become exhausted, which is the condition known as diabetes.
Diabetes is not the only side effect of eating too much sugar and white flour, though; every time the body is flooded with too much pure sugar, it has to draw on its own nutrient stores to properly handle the sugar and remove it from the body. Since most foods that are high in sugar and white flour don’t contain vitamins and minerals, then not only does the body use up its supply, but that supply doesn’t get replenished! If our body doesn’t have enough nutrients, it loses the ability to undergo its most basic functions. The immune system is weakened and can’t protect us. The brain does not function as well, leading to depression, bipolar disorder, or other irrational behavior. Osteoporosis, tooth decay, and kidney damage can all occur as a result of mineral deficiency. Sugar and white flour create an over-acidic condition in the digestive system, leading to candida, acid reflux, and other digestive disorders. The list goes on.
What about weight gain? When sugar is removed from the blood via insulin, it is stored as triglycerides – fat molecules. Since most foods with white flour and sugar are low in density (they don’t contain or water of fiber, and so are not very filling), it’s easy to eat a lot of them – and since they’re pure carbohydrates, they’re very high in calories. Sugar and white flour are the real culprits for high triglycerides and hardening of the arteries. Not only do these simple carbohydrates get stored in our bodies as fat, making it very easy for us to gain weight, they make it very easy for us to succumb to a heart attack. Nevertheless, you’ll be hard-pressed to find a bread product that contains 100% whole wheat flour, instead of white flour, or to find any food product at all that doesn’t contain sugar, high fructose corn syrup or some other form of sugar.
A good way to distinguish between natural carbohydrate foods and processed ones is to refer to them as “complex carbs” and “simple” carbs. The former include whole grains, beans, fruits and vegetables. Whole wheat flour is a complex carbohydrate because, even though the wheat has been ground into flour, the fiber and wheat germ have not been processed out. Fruit and vegetable juices, even though they have been processed a little (fiber has been removed), still contain a lot of water, vitamins and minerals.
Simple carbohydrates are white flour, sugar (in all its forms), and the foods made from these ingredients. You don’t have to avoid them 100% of the time; in fact, how much you choose to eat simple carbohydrate-containing foods is up to you. But if you notice symptoms of fatigue, poor digestion or depression, if you have an erratic energy level, if you’re gaining a lot of weight, or if you’re at risk for heart disease – in fact, if you have any health concern at all – I suggest you reduce your intake of these foods and observe whether your health improves.
What if I like sugar and white flour?
Because of the high energy and mood boost they provide, sugar and white flour are tough to kick. A good place to start is to use more whole wheat flour and natural sweeteners (raw honey, barley malt, agave nectar, brown rice syrup, maple syrup and molasses). Here you have sugar and starch in a form that digests pretty quickly, but not so quickly that your blood is flooded with glucose. Whole grains, starchy vegetables and fruit are not as sweet as most processed foods, but you’ll soon crave them for the balanced mood and energy they give you and you’ll begin to notice their more subtle flavors.
Another group of foods you can eat to control your craving for simple carbs is the high-fat foods. Many of our cravings for pastries and pasta come from the fact that we’ve eliminated fat from our diets, and so we don’t have a satisfying, long-lasting form of energy. Adding in more fat will actually make us more satisfied and cut down on the number of calories we eat in the end. Refer to the Understanding Fat article from last month for a guide to including fat in your diet.
Even though carbohydrates are healthy when found in whole, natural foods (in which condition they are known as “complex carbs”), they will cause weight gain and other health problems when eaten in the pure forms of white flour and sugar (“simple carbs”). I should point out that I don’t completely abstain from simple carbs. If I’m actually going to be using the energy they provide, then they’re not as bad. In the summer, when we need less food and prefer food that is less dense and heavy, more pasta and bread is okay. Let’s not forget that sugar really is delicious, even though I’ve essentially accused it above of being America’s No.1 killer. What’s important is that if you eat some simple carbs, make sure that you also eat some highly nutritious foods like whole grains, fruits and vegetables. These will keep your system healthy and help your blood sugar stabilize. Sugar and white flour are still natural foods in the sense that they come from grains and vegetables (sugar is far, far better than artificial sweeteners that the human body cannot digest); they’re just very extreme foods that can put your body out of balance. Making sure that your diet is balanced and that your intake of simple carbs is moderate is key for living a long, healthy life at your natural weight.