Understanding Carbohydrates

Understanding Carbohydrates
September 22, 2014 No Comments » Nutrition Brian Fulton


*The fact source for this article is THE STARCH SOLUTION by Dr. John McDougall. Roedale Inc. 2012. Dr. McDougall has written and lectured extensively on the role of carbohydrates in the human diet. There is no one with more knowledge or clinical experience in the area of carbohydrates on the planet. His 2012 book, The Starch Solution details the importance of Starch in the human diet, both historically, and in present day. As a massage therapist, I cannot offer nutritional advice. What I can say from my personal and clinical experience is that what you put in your body is one of the most important contributors to health, along with exercise and adequate sleep. Many a patient with health issues will see noticeable improvement when altering their diet. As a result, I feel it is important to learn from subject experts in these matters, such as Dr. John McDougall. Knowledge is power, and once you understand how your body works, you will be in a much better position to improve your personal health. 


How did “Carbs” become a Dirty Word?

These days you hear the word ‘carbs’ thrown around like a dirty old sock. Just what are carbs? Well, carb is short for carbohydrate. As the name carbohydrate suggests, these are biological compounds consisting primarily of carbon, hydrogen and oxygen. Carbohydrates, is a macronutrient that is essential to our diet. The other two macronutrients are protein and fat.  Carbohydrates provide energy for the body, fats are an energy storage compound, and proteins are used to build body tissue. Each macronutrient does much more than this, but this is the basic function of each nutrient.

Are there different types of carbs?

A resounding YES! What all carbohydrates have in common is that they all contain carbon, hydrogen and oxygen as their essential constituents. The primary difference between simple and complex carbs is the size and arrangement of the molecules. Complex carbs contain more fibre, which aids digestion and slows the release of the glucose into your bloodstream. In nature, all simple carbohydrates are surrounded within a matrix of fibre.

As mentioned, carbohydrates are divided into two basic groups; simple carbohydrates known as sugars, and complex carbohydrates. As carbohydrates become increasingly complex, the sugars that they contain are released more slowly into the bloodstream by our digestive system. Complex carbohydrates are typically packaged in insoluble fibre, which have a laxative effect and add bulk to the diet.

1) Sugar- The Simple Carb

Sugars are carbohydrates that contain either six or twelve carbon atoms, and are typically encountered in fruits (as fructose) but can also appear in woody plants, as is the case with sugarcane, or maple syrup. Above is the six-carbon sugar molecule, glucose. All carbohydrates and all nutrients (fats, proteins) for that matter eventually get broken down into this simple molecule so that they can be burned as energy in the body. Therefore, as you can see, sugar is not bad per se, because this is what the body needs for energy. The problem with eating simple sugars (e.g table sugar) is that these sugars are not surrounded by fibre. As a result, your blood sugar levels immediately rise, which causes insulin levels to rise. This leads to a series of issues that can have negative consequences for your health. Overall, experts agree that whatever diet plan you are on, whether high carb or low carb, that it is good to keep your insulin levels low. The best way to do this is by minimizing consumption of simple sugars, unless in the case of fruits, they are surrounded by fibre. Even then, fruit should be an addition to your diet, and not the foundation.

2) Complex Carbohydrates- Starchy Vegetables

A subgroup of complex carbohydrates is starchy and non-starchy vegetables. Starches form the basis of plant-based eater’s diet, because as mentioned earlier, we all need glucose for energy, and starch is a sugar that has been stored in long, complex chains. Foods in this group include root vegetables, squashes, grains and legumes. Examples of individual foods in each of these subgroups include:

  • Root vegetables such as potatoes, carrots, parsnips, and sweet potatoes
  • Squashes such as butternut and acorn squash, field pumpkin, summer squash.
  • Grains such as rice, wheat, rye, barley, millet, oats, bulgur, spelt and couscous
  • Cereals are an example of a starchy food typically comprised of grains
  • Corn and maize are also classed as starches are technically considered to be grains
  • Legumes such as peas, beans, lentils, soybeans
  • Beans are a large group of legumes that deliver starch as abundant whole food. Examples of beans include favas, lentils, mung beans, black beans, peas, and chickpeas.
  • There are a few other random complex carbs such as artichokes

Pictured below is a small portion of a starch molecule, Amylose. Amylose molecules typically consist of 200 to 20,000 glucose units that form a helix, as a result of the bond angles between the glucose units.

While many vegetables can be eaten raw, the digestibility of starch is increased when it is cooked.  Raw starch will digest poorly in the duodenum and small intestine, while bacterial degradation will take place mainly in the colon. This is one of the reasons that people associate gas with beans and other starches, because bacterial activity in the colon can often result in creation of gas. The colon sits at the very end of the intestine so it is a short distance for the gas to find its way out of the body. This is also the reason that starches and complex carbohydrates keep blood sugar levels low, because the food has travelled a log way through the digestive system before it is absorbed into the bloodstream.

3) Non-Starchy Complex Carbohydrates

            Non-starchy vegetables are typically high in cellulose, an indigestible carbohydrate known as fibre. These vegetables are often very nutrient dense. Foods in this group include some of the following foods (in alphabetical order): asparagus, bamboo shoots, beans (green, Italian, yellow or wax), beets, broccoli, bok choy, Brussels sprouts, cabbage, carrots, cauliflower, celery, cucumber, eggplant, greens (beet greens, collard, dandelion, kale, mustard, turnip), green leafy vegetables (kale, lettuce, parsley, spinach, Swiss chard), onions, mushrooms, peppers (green, red, yellow, orange, jalapeno), radishes, rhubarb, rutabaga, sprouts, snow peas or pea pods, tomato, turnips, zucchini. This list is not absolute, but covers most of the common non-starchy carbs that North Americans eat.

Foods on the list above have benefit of not just being nutrient dense (packed with lots of vitamins and minerals), but of also not being calorie dense. This means that you could eat most non-starchy complex carbs and never gain weight. As a matter of fact, most of these vegetables do not provide enough calories to sustain you, so you need to also eat starchy vegetable just to sustain your body weight.

Looking at the chart above and the graph below, you can see why it is good to limit oils and fats, and include many complex carbohydrates if you are concerned at all about weight issues. Complex carbohydrates deliver a maximum of nutrients with a minimum of calories.


4) Fibre

Yes!  Even fibre is a carbohydrate. Dietary fibres are very long chains of complex carbohydrates – so complex that they do not get entirely digested. Most fibres eventually end up in the colon and form the bulk of your stool. They are also the primary food for the good bacteria residing in our colon. Many people think fibre is only the husks of grains and the long stringy components in fruits and vegetables, but dietary fibres are present in all plant tissues. Fibre is divided into two types, soluble and insoluble.

Soluble fibre attracts water and form a gel, slowing digestion. Soluble fibre delays the emptying of your stomach and makes you feel full, which helps control weight. Slower stomach emptying levels out blood sugar levels, having a beneficial effect on insulin sensitivity, which may help control diabetes. Soluble fibre can also help lower LDL (“bad”) blood cholesterol by interfering with the absorption of dietary cholesterol if you eat food of animal origin.

Insoluble fibre is considered to be gut-healthy fibre because of its laxative effect. It adds bulk to the diet, helping to prevent constipation. These fibres do not dissolve in water, so they pass through the gastrointestinal tract relatively intact. Insoluble fibre is mainly found in whole grains and vegetables, as opposed to fruit, which only has soluble fibre.

Carbohydrates are Fuel!

            Something that needs to be understood by anyone demonizing carbs is that the body runs on glucose, and its preferred fuel is carbohydrates. The body can burn fats, but to do so you must keep your blood sugar extremely low. This means no sugar whatsoever in your diet (either in your coffee, your drinks, or in any food that you eat), and it means no sugary dessert items for you, or the fats are likely to be stored on your body. Alternatively, the body can break down proteins for food, but the by-products of proteins are acidic, and this leads to osteoporosis, and puts a strain on our kidneys. The body, just like us is rather lazy, and it would prefer carbohydrates as its energy source. The body also does not like to store excess carbohydrates as fat, as that conversion requires about 30% of the calories consumed. Instead, it prefers to burn them off as heat, and energy. As a result, excess carbohydrates do not tend to get stored as fat on the body. Carbohydrates create two simple compounds when metabolized; carbon dioxide (CO2) and water (H2O). This is what makes carbs the ultimate clean fuel for your body.


I hope this article has convinced you that ‘carb’ is not a bad word. Carbohydrates are the main fuel source for our bodies, and for our gut bacteria. Carbohydrate-rich foods such include fruits and vegetables, which are arguably the healthiest foods we can eat. The real health concern is not ‘carbs’, but refined foods, whether refined carbohydrate, protein or fat. These are the foods you should try to limit or avoid.

To understand more about carbohydrates, I highly recommend THE STARCH SOLUTION by Dr. John McDougall. His book details the metabolism of carbohydrates and shows how thousands of people have lost weight, reduced their medications and regained their health on a starch-based diet.

The fact source for this article was THE STARCH SOLUTION by Dr. John McDougall. Roedale Inc. 2012

About The Author
Brian Fulton Brian Fulton has been a Massage Therapist in Ontario Canada since 1999. His approach toward health and the human body is broad and holistic in nature. Brian is also the author of The Placebo Effect in Manual Therapy: Improving Clinical Outcomes (available on Amazon)