Many factors, including exercise, stress, and illness, affect your blood sugar levels.

That said, one of the largest factors is what you eat.

Of the three macronutrients carbs, protein, and fat carbs have the greatest effect on blood sugar. That’s because your body breaks down carbs into sugar, which enters your bloodstream.

This occurs with all carbs, such as refined sources like chips and cookies, as well as healthy types like fruits and vegetables.

However, whole foods contain fiber. Unlike starch and sugar, naturally occurring fiber does not raise blood sugar levels and may even slow this rise.

When people with diabetes eat foods high in digestible carbs, their blood sugar levels can surge. High carb intake typically requires high doses of insulin or diabetes medication to control blood sugar.

Given that they’re unable to produce insulin, people with type 1 diabetes need to inject insulin several times a day, regardless of what they eat. However, eating fewer carbs can significantly reduce their mealtime insulin dosage.

Your body breaks down carbs into sugar, which enters your bloodstream. People with diabetes who eat a lot of carbs require insulin or medication to keep their blood sugar from rising too much.

If you have diabetes, reducing your carb intake may be beneficial.

Multiple studies have shown that a daily carb intake of 20–150 grams, or 5–35% of calories, not only leads to better blood sugar control but may also promote weight loss and other health improvements.

However, some individuals can tolerate more carbs than others.

Testing your blood sugar and paying attention to how you feel at different carb intakes can help you find your range for optimal diabetes control, energy levels, and quality of life.