Key takeaways:
There isn’t any good evidence that vitamins or supplements can prevent or treat diabetes by themselves. Some small studies suggest that some supplements show promise, but more research is needed.
Supplements or vitamins can’t replace medications for diabetes. Don’t stop taking prescription medications without talking to a healthcare professional.
Some supplements can cause side effects or they can have negative interactions with other supplements or prescription medications. Make sure to talk to your pharmacist or prescriber before starting any supplements.
Save on related medications
Type 2 diabetes is a medical condition that happens when your blood glucose (sugar) is too high. For most people, it’s a life-long condition. It’s usually managed with lifestyle changes and prescription medications, like oral pills or injectable diabetes medications.
You may see products advertised as “supplements for diabetes” or vitamins that claim to “replace your diabetes medication.” But can over-the-counter (OTC) vitamins and supplements prevent or treat diabetes? You might be intrigued by these claims, but you should also be skeptical. Very few supplements have shown a benefit in treating or preventing diabetes.
Below, we’ll discuss seven common supplements that people use to help with diabetes.
1. Chromium
Chromium is a mineral that’s naturally found in your body. One of its jobs is to help control blood glucose levels. It does this by making insulin more effective. Insulin is a hormone made by your pancreas that prevents blood glucose levels from getting too high. In Type 2 diabetes, your body either doesn’t make enough insulin or it doesn’t respond to insulin the way it should.
What the research says
Some evidence shows that people with diabetes may have low levels of chromium. But it’s unclear whether chromium supplementation can help treat diabetes. A review of over 20 randomized controlled trials (RCTs) — the best type of study to evaluate cause and effect — looked at whether chromium supplements lowered blood glucose and hemoglobin A1C (A1C). In these studies, chromium doses ranged from 1.28 mcg to 1,000 mcg. The most common form used was chromium picolinate.
Overall, the study found that chromium supplements didn’t significantly lower blood glucose or A1C levels.
But one small study showed that taking 1,000 mcg of chromium picolinate may be effective in helping your body respond to insulin (improving insulin resistance). People taking chromium in this study also had less weight gain and lower body fat.
The verdict
Currently, the American Diabetes Association (ADA) doesn’t recommend taking chromium supplements to treat Type 2 diabetes. The available research is inconclusive on whether chromium supplements are a valid treatment option for diabetes.
2. Alpha-lipoic acid
Alpha-lipoic acid (ALA) is an antioxidant. It works by getting rid of free radicals (groups of atoms that can cause damage to your cells). ALA can improve blood flow, reduce inflammation, and lower blood glucose levels.
What the research says
ALA has been studied for treating nerve damage caused by diabetes, also called diabetic neuropathy. In a 4-year study of more than 450 people with diabetes taking insulin, 600 mg of ALA taken orally every day improved symptoms of neuropathy. Another smaller, more recent study showed similar results using the same dose of ALA.
While these studies didn’t show that ALA lowered A1C or glucose levels, another study did. It included over 200 people with diabetic neuropathy, and found that taking ALA improved A1C. But the dose in this study was higher — 600 mg three times a day.
The verdict
There’s some evidence that ALA may improve diabetic neuropathy. It’s usually well-tolerated, but it can cause side effects like headache and heartburn. Don’t take ALA without talking to a healthcare professional. ALA isn’t FDA approved to treat diabetes or diabetic neuropathy, and more research is needed to show how effective it is. Other FDA-approved medication may be better to treat diabetic neuropathy.
3. Vitamin D
Vitamin D is involved in many different processes in your body. It helps keep your bones and muscles strong. It also boosts your immunity and helps maintain calcium and glucose levels.
Your body can make its own vitamin D when your skin is exposed to ultraviolet (UV) light from the sun. Vitamin D is also naturally found in some foods, like oily fish, mushrooms, and egg yolks. It’s often added to foods like cereals and milk, or taken as a supplement.
What the research says
People with low vitamin D levels may have a higher risk of developing Type 2 diabetes. But it’s not clear whether vitamin D supplements can help prevent or treat diabetes.
Preventing diabetes
When it comes to preventing Type 2 diabetes, the research is mixed.
One large study of almost 2,500 people found that people taking 4,000 IU of vitamin D per day didn’t prevent prediabetes from progressing to diabetes. Prediabetes is when blood glucose levels are higher than normal but not high enough for a diabetes diagnosis.
A separate analysis looking at eight studies found that taking more than 2,000 IU of vitamin D per day reduced the risk of prediabetes progressing to Type 2 diabetes. In some people with prediabetes, it also helped glucose levels return to normal. But these results were only seen in people who weren’t considered to have obesity.
Another study that followed more than 80,000 women over the course of 20 years found that taking vitamin D (more than 800 IU per day) along with calcium (more than 1,200 mg per day) supplements lowered the risk of developing Type 2 diabetes by 33%.
Treating diabetes
Whether vitamin D can help treat diabetes is also unclear.
One analysis of over 19 studies found that vitamin D supplementation improved A1C levels and insulin resistance in people with diabetes. People taking vitamin D also needed less insulin. But these benefits were only seen in short-term studies lasting less than 6 months. Longer studies (greater than 6 months) didn’t show the same results.
Another study of over 40,000 people found that vitamin D supplements had no effect on improving blood glucose or insulin resistance in those with Type 2 diabetes.
The verdict
There’s some evidence that vitamin D supplements may help prevent or treat diabetes. But other studies show no effect. More research is needed to understand when vitamin D supplements may be beneficial.
Whether or not you have diabetes, having enough vitamin D levels is good for your health. If you have low vitamin D levels, a healthcare professional may recommend vitamin D supplements. If you’re interested in using vitamin D supplements to prevent or treat diabetes, talk to your healthcare team first. They can help you weigh the risks and benefits.
4. Omega-3s
Omega-3 fatty acids (omega-3s) are polyunsaturated fatty acids (PUFAs). PUFAs are generally considered the most nutritious type of fat. Omega-3s help your body build cells and provide them with energy. Your body doesn’t make enough omega-3s on its own. So, you need to get them from food or supplements.
What the research says
Researchers have studied whether omega-3s can help lower insulin resistance or the risk of developing Type 2 diabetes. So far, this doesn’t seem to be true.
A 2019 review of over 80 RCTs looked at whether omega-3s and other PUFAs could prevent or treat Type 2 diabetes. No significant effect was found. Other studies, including a review of 23 other studies, reported similar results.
However, some evidence shows that omega-3s can reduce the risk of heart disease in people with diabetes. This is important because people with diabetes are twice as likely to develop heart disease.
The verdict
There’s no strong evidence that omega-3 supplements prevent or treat diabetes. But omega-3s are important for overall health, and most people get enough through their diet. Some people may still benefit from taking an omega-3 supplement. Talk to a healthcare professional about whether a supplement is right for you.
5. Magnesium
Magnesium is an important mineral your body needs to function properly. Your body doesn’t make magnesium on its own. You usually get it from food, and it can also be taken as a supplement. Some of magnesium’s main functions are helping your nerves and muscles work well, keeping your immune system strong, and maintaining a steady heartbeat. It also helps regulate blood glucose levels.
What the research says
Low magnesium levels may be more common in people with diabetes. And low magnesium levels may contribute to the progression of prediabetes to diabetes. For example, an analysis of seven studies that included more than 280,000 people found that increasing magnesium intake by 100 mg per day, with food or supplements, lowered the risk of developing diabetes by up to 15%.
But when it comes to treating diabetes, the research is mixed. Some studies show that magnesium supplements may lower glucose levels, while others show no effect.
The verdict
There isn’t enough evidence to know whether magnesium supplements effectively prevent or treat diabetes. If you have prediabetes or diabetes, talk to a healthcare professional about checking your magnesium levels. If your levels are low, they may recommend a supplement. Don’t take magnesium without talking to your healthcare team first.
6. Vitamin C
Vitamin C is found in some foods and supplements. Your body can’t make enough of it on its own. It’s involved in many bodily processes, like maintaining a strong immune system and increasing how much iron your body absorbs from food. Vitamin C also helps protect your body against free radicals.
What the research says
A high level of free radicals may contribute to the development of diabetes. Because vitamin C can protect your body against free radicals, vitamin C supplements have been studied as a treatment option for diabetes.
For example, an analysis of over 28 studies, involving over 1,500 people, found that vitamin C supplements improved blood pressure and A1C levels in people with Type 2 diabetes. But most of these studies were small (less than 100 people per study) and followed people for less than 6 months.
The verdict
There isn’t enough evidence to recommend a vitamin C supplement for people with Type 2 diabetes. Larger and more long-term studies are needed to know whether vitamin C is truly helpful.
7. Herbal supplements
Herbal supplements contain ingredients from herbs and other plants. These products are often labeled as “natural,” and many people use them to try and support their health.
What the research says
You might be curious about using herbal supplements to help manage diabetes. Some herbal products that have been studied for preventing or treating diabetes include:
Most studies on these herbal products are short-term and include only a small number of people. They don’t provide enough data to say whether herbal supplements can help prevent or treat diabetes.
The verdict
We can’t say for sure whether herbal products are effective for preventing or treating Type 2 diabetes. Even though many of these products are labeled as natural, they have side effects and risks. They may also interact with many medications. Talk to a healthcare professional or pharmacist before taking an herbal supplement. They can help you check for drug interactions and help you weigh the risks and benefits.
Other supplements to help with diabetes
In addition to the herbal remedies listed above, several other supplements have been studied for diabetes. But there’s differing amounts of research supporting their use. These supplements include:
Berberine: One small study found that the Chinese herb berberine (Coptis chinensis) lowered fasting glucose, A1C, low-density lipoprotein (LDL), and total cholesterol levels. More studies are needed to confirm these results.
Gymnema sylvestre: A 2023 study in mice showed that the herb Gymnena sylvestre increased insulin production, lowered blood glucose levels, and improved cholesterol levels. But studies are needed to see if it’s useful in humans.
Fenugreek: A meta-analysis from 2023 found that fenugreek improved blood glucose levels and cholesterol. But the study didn’t find significant improvements in insulin resistance or weight loss. There’s not enough evidence to support using fenugreek as a diabetes supplement.
Probiotics: A 2023 systematic review of literature looked at 33 clinical trials on probiotics. The results were mixed. The studies in the review used different types and doses of probiotics, making it hard to draw clear conclusions. While some studies showed promise, more studies are needed.
The verdict
More studies are needed before these supplements can be safely recommended for diabetes. These products may cause side effects or interact with your medications. Talk to a healthcare professional or pharmacist before taking any supplement.
Can vitamins or supplements cure diabetes?
No, vitamins or supplements aren’t proven to cure diabetes. For some people, lifestyle changes may be enough to help manage diabetes. For others, prescription medications are needed. Despite what marketing claims, no vitamin or supplement can replace diabetes medication prescribed by a healthcare professional.
Important safety considerations
It’s important to remember that even natural or herbal remedies can cause harm. Just like you wouldn’t take a prescription medication that hasn’t been tested, herbal remedies can also carry similar safety risks.
Some of the safety considerations around herbal supplements include:
Serious side effects: Some supplements can have serious or irreversible side effects, like kidney or liver damage.
Lack of regulation: Most supplements aren’t regulated and the product may not contain what’s on the label. And without regulation, the concentration may not be accurate or it may have contaminants. If you use a supplement, buy one that has been verified for purity, contaminants, and concentration.
Medication interactions: Many supplements can interact with your other medications. Never stop taking your prescription medications for diabetes on your own. And make sure your prescriber knows about all supplements you intend to take.
Cost concerns: Even if they aren’t a safety risk, you can spend a lot of money on supplements that may not improve your diabetes. Your healthcare team or pharmacist can help you decide if a supplement may be worthwhile, a waste of money, or actually dangerous.
Frequently asked questions
Diabetes is complicated. But what you eat doesn’t have to be. A rule of thumb is to avoid sugary, fatty, or highly processed foods. Instead, choose high-fiber whole grains, low-fat dairy, lean proteins, and lots of colorful veggies and fruits.
If you have Type 1 diabetes, it can’t be reversed because your pancreas can’t make insulin. If you have Type 2 diabetes, the good news is that it can sometimes go into remission. Exercise, weight management, a healthy diet, and managing stress and sleep can all help improve diabetes and bring blood glucose values back to normal.
Unfortunately, there’s no cure for diabetes. Most people will need to take medications for a lifetime. But a combination of medications, exercise, weight management, and a balanced diet can make diabetes more manageable. Some people can even put Type 2 diabetes into remission. This means their blood tests are normal and their risk of complications from diabetes is lower.
Diabetes is complicated. But what you eat doesn’t have to be. A rule of thumb is to avoid sugary, fatty, or highly processed foods. Instead, choose high-fiber whole grains, low-fat dairy, lean proteins, and lots of colorful veggies and fruits.
If you have Type 1 diabetes, it can’t be reversed because your pancreas can’t make insulin. If you have Type 2 diabetes, the good news is that it can sometimes go into remission. Exercise, weight management, a healthy diet, and managing stress and sleep can all help improve diabetes and bring blood glucose values back to normal.
Unfortunately, there’s no cure for diabetes. Most people will need to take medications for a lifetime. But a combination of medications, exercise, weight management, and a balanced diet can make diabetes more manageable. Some people can even put Type 2 diabetes into remission. This means their blood tests are normal and their risk of complications from diabetes is lower.
The bottom line
The labels of some OTC vitamins and supplements claim to treat diabetes. But unless you have a true vitamin deficiency, no supplement or vitamin is recommended by the ADA to prevent or treat Type 2 diabetes. Current clinical studies simply don’t offer enough evidence that these treatments are effective.
If you have questions about using a vitamin or supplement for diabetes prevention or treatment, talk to a healthcare professional. They can help you weigh the risks and benefits.
Why trust our experts?
References
Agathos, E., et al. (2018). Effect of α-lipoic acid on symptoms and quality of life in patients with painful diabetic neuropathy. Journal of Medical Research.
Albert, B. B., et al. (2014). Higher omega-3 index is associated with increased insulin sensitivity and more favourable metabolic profile in middle-aged overweight men. Scientific Reports.
Allen, R. W., et al. (2013). Cinnamon use in type 2 diabetes: An updated systematic review and meta-analysis. Annals of Family Medicine.
American Diabetes Association. (n.d.). Insulin basics for diabetics.
American Diabetes Association. (2022). Facilitating Behavior Change and Well-being to Improve Health Outcomes: Standards of Medical Care in Diabetes—2022. Diabetes Care.
Brown, T. J., et al. (2019). Omega-3, omega-6, and total dietary polyunsaturated fat for prevention and treatment of type 2 diabetes mellitus: Systematic review and meta-analysis of randomised controlled trials. British Medical Journal.
Cefalu, W. T., et al. (2004). Role of chromium in human health and diabetes. Diabetes Care.
Centers for Disease Control and Prevention. (2024). Diabetes and your heart.
Costello, R. B., et al. (2016). Chromium supplements for glycemic control in type 2 diabetes: Limited evidence of effectiveness. Nutrition Reviews.
Gu, X., et al. (2010). [Efficacy and safety of high-dose α-lipoic acid in the treatment of diabetic polyneuropathy]. Zhonghua Yi Xue Za Zhi.
Hartweg, J., et al. (2008). Omega‐3 polyunsaturated fatty acids (PUFA) for type 2 diabetes mellitus. Cochrane Database of Systematic Reviews.
Hu, Z., et al. (2019). Efficacy of vitamin D supplementation on glycemic control in type 2 diabetes patients. Medicine.
Joseph, B., et al. (2013). Antidiabetic effects of Momordica charantia (bitter melon) and its medicinal potency. Asian Pacific Journal of Tropical Disease.
Kim, J., et al. (2023). The effect of fenugreek in type 2 diabetes and prediabetes: A systematic review and meta-analysis of randomized controlled trials. International Journal of Molecular Sciences.
Larsson, S. C., et al. (2007). Magnesium intake and risk of type 2 diabetes: A meta-analysis. Journal of Internal Medicine.
Martin, J., et al. (2006). Chromium picolinate supplementation attenuates body weight gain and increases insulin sensitivity in subjects with type 2 diabetes. Diabetes Care.
Martin, T., et al. (2011). Vitamin D and diabetes. Diabetes Spectrum.
Mason, S. A., et al. (2021). Effects of vitamin C supplementation on glycemic control and cardiovascular risk factors in people with type 2 diabetes: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials. Diabetes Care.
MedlinePlus. (2025). Magnesium in your diet.
Mousavi, S. E., et al. (2021). Association between magnesium concentrations and prediabetes: A systematic review and meta-analysis. Scientific Reports.
Muzaffar, H., et al. (2023). Gymnema Sylvestre supplementation restores normoglycemia, corrects dyslipidemia, and transcriptionally modulates pancreatic and hepatic gene expression in alloxan-induced hyperglycemic rats. Nutrients.
National Center for Complementary and Integrative Health. (2023). Diabetes and dietary supplements: What you need to know.
Nguyen, H., et al. (2024). Alpha-lipoic acid. StatPearls.
Office of Dietary Supplements. (2022). Chromium. National Institutes of Health
Office of Dietary Supplements. (2022). Magnesium. National Institutes of Health.
Office of Dietary Supplements. (2025). Omega-3 fatty acids. National Institutes of Health.
Operation Supplement Safety. (2024). Why is third-party certification important for dietary supplements?
Paladiya, R., et al. (2021). Association of low magnesium level with duration and severity of type 2 diabetes. Cureus.
Paquette, S., et al. (2023). The effects of oral probiotics on type 2 diabetes mellitus (T2DM): A clinical trial systematic literature review. Nutrients.
Pittas, A. G., et al. (2006). Vitamin D and calcium intake in relation to type 2 diabetes in women. Diabetes Care.
Pittas, A. G., et al. (2019). Vitamin D supplementation and prevention of type 2 diabetes. The New England Journal of Medicine.
Salehi, B., et al. (2019). Insights on the use of α-lipoic acid for therapeutic purposes. Biomolecules.
Seida, J. C., et al. (2014). Clinical review: Effect of vitamin D3 supplementation on improving glucose homeostasis and preventing diabetes: A systematic review and meta-analysis. The Journal of Clinical Endocrinology and Metabolism.
Shi, L., et al. (2020). Ascorbic acid supplementation in type 2 diabetes mellitus a protocol for systematic review and meta-analysis. Medicine.
Xu, R., et al. (2020). Effects of green tea consumption on glycemic control: A systematic review and meta-analysis of randomized controlled trials. Nutrition & Metabolism.
Yeh, G. Y., et al. (2003). Systematic review of herbs and dietary supplements for glycemic control in diabetes. Diabetes Care.
Yin, J., et al. (2008). Efficacy of berberine in patients with type 2 diabetes. Metabolism.
Yu, A., et al. (2018). Chinese herbal medicine versus other interventions in the treatment of type 2 diabetes. Journal of Evidence-Based Integrative Medicine.
Zhang, D., et al. (2013). Curcumin and diabetes: A systematic review. Evidence-Based Complementary and Alternative Medicine.
Zhang, Y., et al. (2020). Effects of vitamin D supplementation on prevention of type 2 diabetes in patients with prediabetes: A systematic review and meta-analysis. Diabetes Care.
Ziegler, D., et al. (2011). Efficacy and safety of antioxidant treatment with α-lipoic acid over 4 years in diabetic polyneuropathy: The NATHAN 1 trial. Diabetes Care.
