Q: I’ve recently been diagnosed with prediabetes. Are there foods I should eat to prevent getting diabetes?
An estimated 22 per cent of Canadians have prediabetes and some Canadians may not even know they have it.
Prediabetes is diagnosed when fasting blood sugar (glucose) is higher than normal (6.1 – 6.9 mmol/L), but not yet high enough to be considered Type 2 diabetes (7.0 mmol/L or higher).
It occurs in people who have insulin resistance or whose pancreas can’t produce enough insulin to keep blood glucose in the normal range.
Insulin resistance is when cells in the muscles, fat and liver don’t respond properly to the blood-glucose-lowering action of insulin. Family history of Type 2 diabetes, abdominal obesity and physical inactivity can lead to insulin resistance.
If left unmanaged, prediabetes can cause damage to your blood vessels, nerves and kidneys and, eventually, it may progress to Type 2 diabetes.
The good news: Type 2 diabetes is largely preventable. By making diet and lifestyle changes now, you can prevent or delay prediabetes from progressing to diabetes.
Manage prediabetes, prevent diabetes
Lifestyle modification is the cornerstone of diabetes prevention – the landmark Diabetes Prevention Program, a large randomized controlled trial published in 2002, proved this point. People with pre-diabetes who were assigned to the “lifestyle” group (healthy diet, physical activity, weight loss) dramatically cut their risk of developing Type 2 diabetes.
The following strategies can help prevent prediabetes turning into Type 2 diabetes. (Some may even help reverse the effects.)
Lose excess weight. Being overweight is the strongest risk factor for prediabetes and Type 2 diabetes. Excess abdominal fat can cause fat cells to release inflammatory chemicals which are involved in insulin resistance.
The Diabetes Prevention Program showed a modest 5 to 7 per cent weight loss significantly reduced the risk of developing Type 2 diabetes.
Choose whole grains. There’s convincing evidence that diets rich in whole grains protects against Type 2 diabetes.
The fibre in whole grains leads to lower and slower rises in glucose, meaning they have a low glycemic index. Whole grains also contain nutrients and phytochemicals that may help reduce diabetes risk.
Replace refined (white) grains with whole grains such as oats, quinoa, farro, freekeh, brown rice, millet, oats, de-hulled barley and whole grain pasta.
Choose breads made with whole or cracked grains such as stone-ground whole wheat, wholemeal rye and sprouted whole grains. Whole wheat bread is made with pulverized flour so, like white bread, its starch is quickly converted to glucose.
One-hundred-per-cent bran cereals aren’t technically whole grain since they contain only the bran portion of the grain. But since they’re a concentrated source of fibre that’s lacking in refined cereals, they’re good choices. Plus, they have a low glycemic index.
Add magnesium-rich foods. Studies have found that people with prediabetes who have higher intakes of dietary magnesium have a lower risk of developing diabetes. Magnesium plays an important role in insulin action and insulin sensitivity.
Excellent sources include pumpkin seeds, sunflower seeds, almonds, hemp seeds, tempeh, tofu, black beans, chickpeas, lentils, cooked spinach, Swiss chard and 100-per-cent bran cereal.
Choose the right fats. Emphasize heart-healthy unsaturated fats in your diet, which are thought to have beneficial effects on insulin sensitivity.
Good sources of monounsaturated fats include olive oil, canola oil, peanut oil, avocado, almonds and cashews. Polyunsaturated fats include sunflower oil, walnuts, chia seeds and flax seeds.
Limit added sugars. Avoid sugar-sweetened drinks which have a high glycemic index and are tied to a greater risk of obesity and Type 2 diabetes. Limit cookies, pastries, cakes and other sweets.
Read labels on breakfast cereals, snack bars, flavoured yogurts and condiments. Some brands of “no added sugar” jams, for example, have 5 g of sugar (one teaspoon worth) per serving from fruit juice concentrate, an added sugar.
Be active. Regular exercise can help maintain a healthy weight. Aerobic exercise, high-intensity interval training and resistance training have been shown to improve insulin sensitivity in prediabetes.
Participants in the Diabetes Prevention Program performed at least 150 minutes of moderate-intensity exercise a week (e.g., brisk walking).
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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