Can Vitamins Raise Blood Sugar?

Some vitamin supplements might be unsuitable for people with diabetes.
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Vitamin supplements might provide some health benefits, especially for people with nutritional deficiencies. While vitamin and mineral supplements are usually safe for most people, people with diabetes should avoid taking them without supervision by a doctor. To wit, one of the B vitamins might cause an increase in blood sugar levels.

Blood Sugar Levels

Diabetes affects your ability to convert food into energy. In healthy individuals, insulin production helps the cells absorb glucose. Diabetes can cause a decrease in insulin production, which results in a buildup of glucose, or sugar, in the bloodstream. High blood sugar levels can cause damage to the kidneys, blood vessels, nerves, eyes and heart. Keeping your blood sugar level in a healthy range is an important element in controlling the health risks associated with diabetes.


Vitamins and Minerals

Various types of foods provide natural sources of vitamins and minerals. A well-balanced diet that includes a variety of nutritious foods, such as whole grains, lean proteins, fat-free dairy products, fresh vegetables and fruits, usually provides all the nutrients necessary for optimal health. Supplements might help guard against nutritional deficiencies in individuals who consume insufficient amounts of nutritious foods. Good nutrition is a key factor in managing blood sugar levels, but one type of vitamin might be harmful for people with diabetes.


Niacin, also called vitamin B-3, is a water-soluble vitamin that helps control the production of hormones, reduces cholesterol levels and can improve circulation. Foods that supply this vitamin include beets, salmon, tuna, beef liver, peanuts and sunflower seeds. Although niacin is an important nutrient, the University of Maryland Medical Center warns that it can increase the level of glucose in your blood, possibly leading to a condition known as hyperglycemia. No evidence suggests that any other vitamins, including other B vitamins, can cause an increase in blood sugar levels.



Although most vitamins appear safe for people with diabetes, it is important for you to talk to your doctor before taking any vitamin or mineral supplement, especially one that contains niacin. No evidence suggests that taking any type of dietary supplement can treat diabetes or complications that might occur due to this disease. Taking supplements might require you to adjust your diabetes medications.


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