Because of food manufacturer marketing strategies that oversimplify the low carb diet, carbohydrates have been demonized. But just as there are healthy and unhealthy types fats, there are also healthy (i.e., complex carbs) and unhealthy (i.e., simple carbs) types of carbs. Below is a breakdown of the types of carbohydrates to eat and the types to avoid. However, note that this information does not apply to people who have certain genetic conditions, such as lactose intolerance, galactosemia, or celiac disease, which restrict the body’s ability to metabolize certain carbohydrates (1, 3, 5).
Simple Carbs vs. Complex Carbs
Nutritionists categorize carbohydrates as either simple carbohydrates or complex carbohydrates. One has a short chain of molecules (simple). The other has a longer chain (complex). From a chemistry point of view, all carbohydrates are technically “sugars.” But the sugar most people think of when they hear the word is also considered its own class of carbohydrates – go figure (4, 9, 11). Sugars have short chains of molecules (simple carbs). However, not all carbohydrates are sweet. And not all accompany healthy vitamins and fibre (6, 10). This is where we can start to see a divide between healthy and unhealthy carbs.
For example, table sugar (sucrose – a simple carb), is a sweet and unhealthy carbohydrate because it is not accompanied by fibre or vitamins. However, vegetables and whole grain bread (complex carbs), which are not sweet, are forms of healthy carbohydrates. Why? Because they are accompanied by vitamins, minerals, and fibre (2, 4, 10). However, it is important to note that some complex carbs are often refined (e.g., white flour and pastries). This usually means that their fibre, vitamin, and mineral contents have been stripped and unhealthy sugars have been added. So it can be a bit of a trade-off. Yes, you will probably consume some simple carbs in the form of sugar. But try to eat ones that accompany natural fibre, vitamins, and minerals. Think fruit (good) versus candy (bad). Too easy.
How to identify healthy vs. unhealthy carbs
Another helpful tool is the glycemic index (GI) of foods. Many studies suggest that the GI may be a more effective way to identify healthy forms of carbohydrates (6, 8, 13). Moreover, the simplest way to separate healthy and unhealthy carbohydrates (and most foods for that matter), is to consume foods that grow naturally and avoid processed and refined foods. For example, brown rice, oats, and broccoli are healthy whereas white crackers, pastries, and granola bars are not. Why? Because they are more processed and more likely include added sugar.
Added sugars can be hidden under many names in ingredient lists. Below is a list of some of the most common names for simple carbs, ones you want to minimize in your diet. Importantly, it includes scientific names used by food manufacturers to “hide” sugar from the buyer. Certain prefixes and suffixes of names are important to recognize when determining if food contains added sugars. For example, the prefix “malt-” and the suffix “-ose” refer to sugar. Maltodextrin and dextrose are two examples of sugars added by manufacturers to improve shelf life and taste.
Simple Carbs (1-2 sugar molecules)
Carbs in bold reflect names that are often “hidden” in processed foods.
Additionally, watch out for these in ingredient lists:
- High-fructose corn syrup
- Evaporated cane juice
- Dehydrated juice
- Fruit juice concentrate
- Molasses (treacle)
Here are some foods that contain simple carbs:
- White bread, pasta, and rice
- Replace these with whole grain flour and brown rice
- Cereals made from “enriched wheat flour”
- Replace these with oats and bran
- Table sugar
- Condiments, such as jams, ketchup, and BBQ sauce
- Canned fruit
Keep in mind that simple carbs are also found in foods like apples, peaches, bananas, and all fresh fruit for that matter. This doesn’t make them unhealthy. Because fresh fruits contain vitamins, minerals, and fibre and are grown with minimal human intervention, they’re healthier (2, 7). Other healthier foods that contain simple carbs include raw honey and pure maple syrup.
Complex Carbs (3 or more sugar molecules)
Complex carbs are commonly referred to as dietary starch. They normally contain lots of fibre, vitamins, and minerals. These carbs are most common in whole plant foods but are also found in whole grains. Complex carbs also generally have a low glycemic index (GI). For this reason, they help you release energy at a longer and more consistent rate than simple carbs do (6, 8, 13).
Foods to look for that contain complex carbs include the following:
- All vegetables
- Legumes (e.g., beans, lentils, and peas)
- Whole grain flour in breads, pasta, and couscous
- Oats, bran, and barley
- Brown and wild rice
In sum, it’s a myth that all carbs are unhealthy as some low carb diet plans suggest. However, it’s important to avoid simple carbs, especially those containing refined flour and sugar, and eat complex carbs and low-GI foods. People should also be wary of artificial sweeteners, especially aspartame. There aren’t many longitudinal studies conducted on aspartame, and some early evidence suggests that it may have negative health effects (12). But most importantly, people need to develop a diet around carbs that reflects their own metabolism, fitness level, and genetics to achieve their goals.
Kinesiologist & M.Teach
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