Carb Intolerance

Can’t lose weight? You may have some carb intolerance.

By Jackie Buell, RD

If you made yet another resolution to lose weight in the New Year, you’re certainly not alone. It is estimated that only 8 percent of those who make resolutions actually keep them, and weight loss can be particularly challenging.

One thing to consider if you have tried to eat healthily and have actually made time to exercise this year and still aren’t losing weight is how your body tolerates carbohydrates.

Most of us have heard of people being lactose or gluten-intolerant, but your body can be intolerant of other carbs, as well. In this case eating even small amounts of certain carbs can cause bloating, fatigue, abdominal cramps, and poor digestion, leading to heartburn. What we don’t know as much about is whether this also affects insulin levels differently and may prevent shedding that weight.

It is really easy to eat too many carbohydrates, and doing so is bound to raise insulin levels to promote fat storage. To counteract this, some diets call for cutting out all carbs and eating only proteins, while others suggest limiting “total carbs” to only a few grams per day. Newer renditions of this low-carb lifestyle include eating an optimal amount of protein and filling the rest of the diet with some healthy fats to teach the body to burn more fat.

But the fact is carbs do not all fall into one category. There are many types of carbohydrates, which are broken down by various enzymes in different parts of the digestive system. Depending on the type of carb—whether a sugar, a starch, or fiber—it will be processed by different enzymes in the saliva, pancreas, or small intestine.

Thinking about the different categories of carbohydrates and their varying nutrient density can be helpful in making healthy choices. Eating complex carbohydrates like beans or including dairy in the diet contributes many nutrients, likely making consuming that carb a good strategy. Eating white pasta, white bread, or empty-calorie snack bars, however, is not likely worth the calories or insulin load. Why consume or overconsume the carbs that are flaring your insulin without much advantage to your health?

Before starting any diet or physical activity program, it is best to visit your doctor for a comprehensive physical. There are tests and measurements that your doctor can perform that will immediately indicate if you are at risk for some insulin resistance or carb intolerance.

For example, metabolic syndrome is a diagnosis that might indicate some carb intolerance. Metabolic syndrome is defined by having three or more of the following:

  • Waist circumference of more than 35 inches for women (40 inches for men)
  • Blood pressure reading for either number that is greater than 130/85
  • Low HDL (high-density li­poprotein, “good” cholesterol)—less than 40
  • Fasting blood glucose of more than 100
  • Triglyceride levels above 150

Even with that information, however, pinpointing your tolerance of carbs may take some work on your part. If you often seem bloated or distended or find it nearly impossible to lose weight, no matter how hard you try, the following tips can help identify the potential of carb intolerance.

Keep a food and workout journal. Be keenly aware of what you are eating by writing it down and looking closely at the ingredients. If a food you are eating has you feeling bloated or lacking energy, recognize it and find a more compatible substitute. The journal will also allow you to track whether you are getting enough exercise to balance your food habits.

Eat fewer carbs, but don’t ban them completely. An initial approach might be to ensure that your portions of carb foods—including healthy dairy, fruit, and grains— are reasonable. If you feel better as you move carbs out of your diet, it might help you to think about your tolerance level. Each person has a different metabolism, and a low-carbohydrate diet works very well for some people. It is important to note, however, that a low-carb diet does not mean eating only protein. Consuming healthy fats and remembering to include a lot of vegetables is important for antioxidant and fiber health.

Be less refined. Avoid refined and processed sugars that are added to things like sodas, fruit drinks, and desserts, and learn to decipher food labels. Foods that contain high-fructose corn syrup, dextrose, and even raw sugar should be eaten only sparingly. Instead stick to foods with more complex carbohydrates, like nuts, whole grains, and raw fruits and vegetables. Again, let nutrient-dense foods rule.

Eat more often, not less often. Many of us think that the key to losing weight is to avoid eating food, but some people respond well to eating more frequently, just in smaller quantities. I tell my patients to eat four to six small meals per day to regulate their blood sugar and keep their appetite under control. Anyone who has dieted knows that cravings are powerful things; avoid them by eating good foods often. Including a little protein and fat in each meal is important.

If you’re resolved to lose weight, you may want to start with a trip to the doctor instead of a membership at the gym. Together the two of you can get a better handle on how carbs might affect your body and come up with a plan that is more likely to still be working this time next year. A registered dietitian can be a great teammate to help you consider a diet plan that works for you over the long haul.


 

Jackie Buell, RD, is an assistant clinical professor of health and rehabilitation sciences at The Ohio State University (OSU) Wexner Medical Center, where she specializes in sports nutrition. Her dual background in athletic training and nutrition is reflected in her research on issues related to athlete weight, including female athlete triad and metabolic syndrome, as well as current topics like iron and vitamin D status in the athletic environment. Buell is credited with the continuous growth and development of the Sports Nutrition program for the Ohio State University athletes from 2002 to 2014. Her current clinical focus is to grow the sports nutrition specialty within OSU Sports Medicine.