Understanding blood sugar since 2011

If you want to manage your A1C, what you eat is the single biggest lever you control. Food directly determines how much glucose enters your bloodstream — and over weeks and months, those patterns show up in your A1C reading.

The good news: you don't need a complicated diet. The foundations are the same whether you have diabetes, prediabetes, or are just trying to stay healthy.

The core principles

Three things matter most: the quality of your carbohydrates, the size of your portions, and the timing and pace of your meals.

The plate method

A simple visual: half your plate non-starchy vegetables, a quarter lean protein, a quarter whole grains or starchy vegetables. Add a small serving of fruit or dairy on the side. This works without counting anything.

Foods that help

Vegetables & legumes

  • Leafy greens (spinach, kale, chard)
  • Broccoli, cauliflower, Brussels sprouts
  • Chickpeas, lentils, black beans
  • Sweet potatoes (in moderation)

Fruits

  • Berries (highest fiber, lowest sugar impact)
  • Apples and pears with skin
  • Citrus fruits

Proteins

  • Salmon and other fatty fish
  • Skinless chicken and turkey
  • Eggs
  • Greek yogurt (plain, unsweetened)
  • Tofu and tempeh

Whole grains

  • Oats (steel-cut or rolled)
  • Brown rice, wild rice, quinoa
  • Whole-grain bread (check labels)

What about coffee and tea?

Both have been studied extensively and both are associated with lower risk of developing type 2 diabetes. The Leibniz Center for Diabetes Research found that drinking four cups of tea daily was associated with a 20% lower risk of type 2 diabetes in a study of 12,000 patients across Europe.

One caveat: caffeine is a stimulant and can affect blood glucose, especially on hot days when you're also active. If you're exercising in the heat, be mindful of heavy caffeine intake.

What to minimize

You don't have to eliminate anything forever. But the following items raise A1C significantly if they're regular parts of your diet:

Related guides

For specific audiences, see our Guide to Fruits and Vegetables for Seniors and our Guide to Healthy Fats and Oils for Seniors.

Diet works best in combination with physical activity. See our exercise guide for the other half of the equation.

This page is for general education and is not a substitute for personalized medical or nutritional advice. If you have diabetes or other medical conditions, work with your healthcare provider or a registered dietitian on a plan that fits your needs.