I don’t recall a time in my career as a dietitian when carbohydrates haven’t been vilified for one reason or another. They’re accused of making you gain weight, hindering weight loss, even causing diabetes.
The notion that eating carbohydrates can hamper certain health goals has led many people to eat less of them and, in some cases, drastically so.
While some types of carbohydrates should definitely be limited, such as added sugars and refined grains, ousting others can rob your body of nutrients, drain your energy, worsen your mood and, possibly, affect your long-term health.
Here’s what to know about carbohydrates (or carbs), along with clues you might need to eat more of them.
What exactly are carbohydrates?
The term carbohydrate encompasses starches, sugars and fibre.
Starches are found in wheat, barley, rye, rice, oats, corn, pulses (such as chickpeas, kidney beans, lentils) and starchy vegetables (such as potatoes, winter squash, turnip, green peas).
Sugars can be naturally occurring in fruit (fructose) and milk products (lactose) or they can be produced commercially, such as table sugar, molasses and high-fructose corn syrup. Other sugars include honey, maple syrup and fruit juice concentrate.
Ultimately, starches and sugars end up in your bloodstream as glucose, the only form of energy the body can use immediately.
Unlike starches and sugars, the body can’t digest fibre, found in whole grains, pulses, fruits, vegetables, nuts and seeds. Fibre promotes satiety and nourishes gut microbes, which is thought to provide a range of beneficial health effects.
Diets higher in fibre and whole grains are associated with a lower risk of cardiovascular disease, Type 2 diabetes and colorectal cancer.
Eating too few carbohydrates can produce more immediate side effects, too.
The following symptoms can be warning signs that you need to add healthy carbs to your diet. If you experience any of these symptoms regularly, check in with your doctor to rule out other possible causes.
You feel shaky between meals
Too little sugar in the bloodstream, called hypoglycemia, can cause shakiness, weakness, irritability and headache. It can be a concern for people with diabetes taking certain medications, but it can also affect people who don’t have diabetes.
Altering what you eat can help prevent blood glucose from dropping too low. Include low glycemic-index (GI) carbohydrate foods at meals and snacks, which release glucose slowly into the bloodstream. (Including protein at meals is important, too.)
Examples include steel-cut oats, whole grain sourdough bread, whole wheat pasta, yogurt, apples, pears, oranges, dried apricots and beans and lentils. Unlike added sugars and refined grains, these foods don’t lead to a sharp rise in glucose and insulin, which can trigger blood sugar to fall prematurely.
You feel hungry soon after lunch
The combination of eating smaller portions and cutting carbs to lose weight can leave you with a grumbling stomach by early afternoon – and food cravings later on.
A common mistake: Eating a skimpy breakfast followed by a salad-and-protein-only lunch.
The solution is usually adding the rightsized portion of carbohydrates to lunch, such as whole grains, chickpeas, lentils and/or whole fruit. Making sure breakfast includes carbohydrates and protein also helps.
It is true, you can lose weight without giving up carbs.
You lose steam midway through your workout
Glucose in the bloodstream that’s not used for energy right away is converted to glycogen in muscles (and the liver) for future use.
Muscle glycogen is the primary fuel for all types of exercise – aerobic workouts, strength training and stop-and-go sports. Having low glycogen stores can result in early fatigue and less effective training.
Include nutritious carbohydrate-rich foods at meals and snacks to keep your muscle glycogen topped up. The more vigorous you exercise, or the longer you workout, the more carbohydrate you need.
Medically speaking, constipation is defined as having fewer than three bowel movements a week. A low-fibre diet is often a cause and adding more of it to your diet can remedy, and prevent, the condition.
Whole grains, nuts and many fruits and vegetables contain insoluble fibre, the type that retains water and adds bulk to stool, helping it pass more quickly through the colon.
Excellent sources of insoluble fibre include wheat bran, bran cereal, whole grain rye bread, whole wheat pasta, freekeh and quinoa. Apples, berries, figs, kiwifruit, mango and avocado are also good sources, as are carrots, parsnips, green peas, spinach, pinto beans, chickpeas and navy beans.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on Twitter @LeslieBeckRD
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