If you want to avoid diabetes—and who doesn’t?—then choosing foods that are low in sugar and fat is probably your mantra. But there’s more to the diabetes story. 

Exciting research: One of the most effective—but least talked about—ways to protect against diabetes is to load up on antioxidants, those ultra-­healthy substances (think vitamins C and E, beta-carotene and others), ­according to a growing body of scientific evidence. Why antioxidants are such heavy hitters in preventing this increasingly widespread disease… 

Attacking the Root Cause

No doubt you have heard of antioxidants and their archenemy, free radicals. In healthy numbers, these volatile oxygen molecules roam our bodies performing useful functions such as fighting infection. But in excess numbers, these and other similar molecules can cause all kinds of damage to the body.

Enter antioxidants. These substances, which are found in the highest amounts in certain vegetables and fruits and are naturally produced by the body, keep the rogue oxygen molecules in check. When antioxidants run low, however, the result is oxidative stress, a condition widely known to hasten aging, heart disease and cancer. 

What you may not realize: Oxidative stress has also been linked to insulin resistance, a major cause of type 2 diabetes. When insulin resistance develops, it means that the hormone insulin is not working effectively to get glucose (sugar) into the cells of your body to give them energy. This leads to too much sugar in the blood—with the result being diabetes or its precursor, known as prediabetes.

The Antioxidant Fix

If you are concerned about diabetes, you may think that the easiest solution is to take an antioxidant supplement, such as vitamin C. But the latest research shows that’s not true. 

In fact, research has shown that supplements are of limited or no use to most people struggling with blood sugar control—and may even cause harm. For example, vitamin C supplements were shown to interfere with the diabetes-fighting benefits of exercise—in part by blocking the body’s production of its own natural antioxidants. The solution is as simple as choosing the right foods.

Getting the Right Foods

When choosing foods to help prevent diabetes, you want to load up on those that contain “phase 2 antioxidants,” nutrients that stimulate the body’s antioxidant defenses by activating a protein called nrf2 (short for nuclear factor erythroid 2-related factor 2). Nrf2 is a powerful switch that can turn on genes inside your cells, triggering the production of natural antioxidants. Among the best nrf2 boosters…

• Cruciferous vegetables such as broccoli, brussels sprouts, cauliflower and cabbage contain high levels of sulforaphane, a potent phase 2 antioxidant. Goal: Two or more cups daily. 

• Blueberries contain high levels of pterostilbene, an effective nrf2 activator. Goal: One cup daily. 

• Fatty fish. Salmon, tuna, sardines, mackerel and herring contain omega-3 fatty acids that boost nrf2. Goal: Eat fatty fish (3 to 4 ounces per serving) three times a week.

• Green tea contains a wide array of antioxidants and stimulates nrf2 activity. Replace soda and juice with green tea. Goal: Two to three cups daily. 

• Curcumin. The active ingredient in the Indian spice turmeric is a powerful nrf2 stimulator that also has anti-­inflammatory effects. Goal: Season with curcumin instead of salt. 

A Diet That Works

What does an antidiabetes diet look like? One version of this eating style is the Rural Asian Diet, developed at the Joslin Diabetes Center. The overall mix calls for 70% complex carbs (such as vegetables and whole grains)…15% fat…and 15% protein, including at least 15 g of fiber for every 1,000 calories. 

Important: When it comes to limiting oxidative stress, don’t forget to also exercise regularly…reduce stress…stop smoking…and get plenty of sleep.