What Supplements Can Lower Blood Sugar? (2023)

Certain vitamins and supplements are thought to help lower blood glucose (sugar) in people with diabetes or prediabetes. While it is well known that changes in diet can help reduce blood sugar in people with type 1 and type 2 diabetes, the benefits of over-the-counter supplements remain largely unproven, according to the American Diabetes Association.

Even so, many people turn to these natural remedies to either support the recommended treatments or reduce their risk of getting diabetes.

This article takes an unbiased look at what the current research says about 13 "anti-diabetes" supplements sold online and in drugstores in the United States.

Aloe Vera

Aloe vera has long been purported to have blood sugar-lowering properties.

A 2016 review of eight clinical studies found that oral aloe vera improved glycemic (blood glucose) control in people with prediabetes and type 2 diabetes. Even so, the researchers noted that the quality of the research was low and that more randomized controlled trials are needed to support the early findings.

Another review in 2016 suggested that aloe vera was particularly useful in lowering blood sugar levels in people with prediabetes. As with the other study, the authors conceded that the findings were inconsistent and that more research is needed before any recommendations can be made.

How to Use Aloe Vera

Aloe vera comes in a juice you can drink, as well as extracts and dietary supplements. There are no guidelines for the appropriate use of aloe vera in any form, but never consume more than eight ounces of aloe vera juice per day to avoid diarrhea.

Precautions

Aloe vera juice can cause diarrhea, hives, and cramping. This is due to latex found in the plant's leaves. To avoid these symptoms, choose products made from the inner part (fillet) of the aloe vera plant rather that the latex-rich leaves.

Aloe vera can also interact with drugs like antidepressants and opioids. These interactions can either decrease the activity of the other drug (making it less effective) or increase the activity of the other drug (increasing the risk of side effects).

Cinnamon

A 2020 study suggested that cinnamon, made from the bark of the cinnamon tree, may help control blood sugar in people with prediabetes.

The 12-week study published in the Journal of the Endocrinology Society evaluated 54 adults with prediabetes who were given either three daily 500-milligram (mg) doses of cinnamon or three daily doses of a sham drug (placebo). According to the researchers, those who received cinnamon had lower sugar levels after overnight fasting than those given the placebo.

How to Use Cinnamon

Cinnamon is taken by mouth as a supplement. Most manufacturers recommend doses ranging from 250 mg to 500 mg twice daily.

Precautions

When taken at high doses, cinnamon can cause heartburn, indigestion, burping, nausea, and diarrhea. Some types of cinnamon contain a compound called coumarin which can raise liver enzymes. Consult your healthcare provider before taking cinnamon supplements if you have liver disease.

Vitamin D

Vitamin D, or the “sunshine vitamin,” is generated when your body is exposed to the sun’s ultraviolet rays. It helps strengthen your bones. Vitamin D deficiency can have wide-ranging negative effects on your body, including a higher risk of type 2 diabetes.

A 2019 study found that vitamin D may improve insulin sensitivity, lowering glucose levels and the risk of developing type 2 diabetes. The researchers examined 680 women in Brazil from the ages of 35 to 74. They found that vitamin D supplements increase glucose levels. Regular sun exposure was also tied to lower blood sugar levels.

A 2015 study found that a two-month regimen of taking daily vitamin D supplements resulted in participants having both improved fasting blood sugar and blood glucose levels.

Another study from 2016 echoed these findings. While emphasizing that more research needs to be conducted, the authors concluded that vitamin D supplementation may have beneficial effects on controlling the glycemic indicator.

How to Use Vitamin D

Consult with your doctor about the best dosage of vitamin D for you before using it. It’s recommended that you embrace a well-rounded, nutritious diet to ensure that you get all the nutrients your body needs.

Precautions

Vitamin D supplements may interact with various medications, including:

• Xenical, Alli (orlistat): Weight loss drugs can reduce vitamin D absorption when included with a reduced-fat diet.
• Statins: Due to the fact that vitamin D is derived from cholesterol, various statins may actually impair vitamin D synthesis. There may also be a potential decrease in absorption of certain statins with higher doses of the vitamin.
• Deltasone, Rayos, and Sterapred (prednisone): Steroids like prednisone that are prescribed for inflammation can reduce calcium absorption and impair the metabolization of vitamin D.
• Hygroton, Lozol, and Microzide (thiazide diuretics): When combined with vitamin D, these diuretics can lead to hypercalcemia, where calcium levels are too high, particularly in older adults.

Magnesium

Magnesium is a common mineral that plays a central role in regulating your blood pressure, muscle function, heart rhythm, and blood sugar levels.

In general, diets with higher amounts of magnesium are tied to a lower risk of diabetes, which suggests it plays a role in glucose metabolism.

A 2019 study showed that taking oral magnesium supplements reduced participants’ resistance to insulin and improved glycemic regulation in people living with type 2 diabetes.

How to Use Magnesium

Magnesium supplements come in different forms. Some include magnesium oxide and citrate, as well as chloride. It’s recommended that you take magnesium with a meal each day for better absorption.

Precautions

Magnesium supplements can interact with medications, including antibiotics and diuretics. Consult with your healthcare provider and give them a list of medications you’re currently on to avoid any interactions.

Bitter Melon

Bitter melon, or Momordica charantia, is a fruit that has been used for medicinal purposes in Chinese as well as Indian medicine for centuries. It is often used as an herbal remedy for diabetes because it contains active anti-diabetic substances which are said to lower blood glucose levels.

There are not a lot of conclusive studies reviewing the impact of bitter melon on lowering blood sugar levels, but a 2011 report does hypothesize that bitter melon capsules contain at least one ingredient for inhibitory activity against the production of a specific enzyme—11β-HSD1. This is said to break down cortisone to the active form cortisol, leading to hyperglycemia. The authors theorize this inhibitory property might be why this fruit is said to possess anti-diabetic properties.

The sample sizes of most studies included in a separate 2013 review were incredibly small. It is hard to definitively say that bitter melon is as effective as more vetted supplements and herbal remedies for lowering blood sugar. The authors concluded that the research is encouraging, but calls for more studies to investigate the benefits of bitter melon.

How to Use Bitter Melon

Bitter melon can be eaten as a whole fruit or squeezed into a juice, or its seeds can be crushed into powdered form for consumption. Bitter melon extract is also sold as an herbal supplement.

Precautions

For those considering using bitter melon as a supplement to lower blood glucose levels, limit how much you eat or take, since consuming it in excess can result in diarrhea as well as mild abdominal pain.

Gymnema

Gymnema, or Gymnema sylvestre, is a perennial woody vine found in tropical regions of India, China, Australia, and parts of Africa. It is often used in Ayurvedic medicine.

Research has shown that this plant can diminish a person’s craving for sugar. Additionally, it can lower the rate of the body’s sugar absorption—playing a role in the treatment of diabetes.

One study out of 2017 looked at the impact of taking 200 to 400 mg of gymnemic acid. It showed that taking this substance reduced the intestines’ sugar absorption.

An earlier study in 2010 looked at participants with type 2 diabetes given 500 mg of gymnema every day for a period of three months. The researchers found that participants’ glucose levels, both fasting blood sugar and levels after meals, lowered. Also, diabetic symptoms such as thirst and fatigue were less prominent, lipid levels improved, and levels of a type of hemoglobin bound to glucose known as glycated hemoglobin decreased.

How to Use Gymnema

Gymnema can be taken in the form of an extract, tea, or powder. You can also chew on the leaves of the plant itself and can find gymnema in capsule form. If you opt for the capsule form of gymnema supplements, you should consult with your doctor or healthcare provider about the best dosage for you.

Precautions

There isn’t enough research out there about whether people who are pregnant or breastfeeding should take extra precautions. As always, consult with your provider before using any new supplement.

Given that gymnema can regulate blood sugar levels in people with diabetes, look out for signs of hypoglycemia and monitor your blood sugar. Since it can impact blood sugar levels, it might affect blood sugar control during as well as after a surgery. Consult your provider and let them know you are using this supplement before going in for any surgical procedure.

American Ginseng

American ginseng, also called Panax quinquefolius, is an herb commonly used in traditional Native American and Chinese medicine. It is believed the ginseng plant’s roots can prevent infections and treat conditions like cancer and diabetes.

One 2018 study of 39 people living with diabetes found that the herb, coupled with fiber, helped lower blood sugar levels over the course of 12 weeks. However, the authors made it clear that more research needs to be done to better understand the health impacts of this herbal supplement.

That was the similar conclusion of the authors of a 2014 review of 16 different studies. They looked at randomized, controlled trials that took place for a month or longer among people with and without diabetes. They found that those who used ginseng herbal supplements had significantly improved blood sugar levels compared to the control groups.

How to Use American Ginseng

You can get ginseng as an extract or in capsule form. As with other supplements, herbal treatments like ginseng are highly unregulated and there is no standardized dosing to adhere to. Consult your doctor or healthcare provider about best ways to incorporate this herbal supplement into your diet or regimen.

Precautions

Ginseng has been found to have moderate interactions with diabetes medications like insulin and sulfonylureas, including Amaryl (glimepiride), DiaBeta (glyburide), and Glucotrol (glipizide). These interactions could result in hypoglycemia.

Ginseng products may also interfere with Coumadin (warfarin), a blood thinner.

Chromium

Chromium is a natural mineral found in certain foods. It comes in two forms: hexavalent (chromium 6+) and trivalent (chromium 3+). The trivalent form is what you will most likely encounter and is found in foods. However, you should steer clear of its hexavalent form, which is toxic and found in industrial waste and pollution.

A 2014 review found favorable effects of chromium supplementation on glycemic control in patients with diabetes. This was echoed years earlier by an older review that came to a similar conclusion, but as with many of the supplements covered here, the authors advised caution and that more research should be carried out to better determine the health effects of chromium.

How to Use Chromium

There is no established Recommended Daily Allowance (RDA) for chromium. Generally, multivitamin or mineral supplements that contain chromium have doses of 35-120 mcg. You can also find supplements that are exclusively chromium, which provide 200 mcg to 500 mcg of the mineral. Some can go as high as 1,000 mcg, but they are not as common.

Precautions

Some medications may interact with chromium supplements. Insulin is one, as taking it with chromium increases the risk of hypoglycemia. Metformin and other diabetes medications taken together with chromium also carry this risk.

A small study showed that chromium picolinate supplements taken at the same time as the hypothyroidism treatment levothyroxine can delay that drug’s absorption by over six hours.

Berberine

Berberine is a chemical compound extracted from the roots, stem, and bark of plants. It’s included as an ingredient in a wide range of supplements and has been a staple of traditional Chinese and Indian medicine. It has been used in the treatment of type 2 diabetes, hypertension, and hyperlipidemia.

A 2019 study examined 80 people who were in the hospital for metabolic syndrome from January 2017 to December 2017. They were divided in half into a control group and an observation group, with the control group being treated with Western therapies and drugs and the observation group with berberine-based therapy. The researchers concluded that the combined application of berberine in patients with metabolic syndrome can effectively regulate blood glucose and blood lipid, alleviate insulin resistance, and reduce the level of inflammatory response in the body.

Berberine has been shown to be incredibly effective and potentially on the same footing as more traditional treatment options. A 2014 meta-analysis concluded that berberine is so effective that it might be a good alternative to more traditional medicine. The authors conclude that the supplement is a good option for treating conditions like type 2 diabetes in people of lower socioeconomic status due to the fact that it is relatively low cost and and is effective with no serious side effects.

As with other herbal supplements, more research on the benefits of berberine needs to be conducted.

How to Use Berberine

Taking 500 mg of berberine two to three times a day for up to three months could be an effective way to control blood sugar levels.

Precautions

Berberine does have some interactions with medications you may already be taking. Keep in mind this is not an exhaustive list and that there may be other interactions:

• Neoral, Sandimmune (cyclosporine): Berberine may decrease the speed with which your body breaks down this medication, which could cause it to build up and exacerbate side effects.
• Diabetes medications: Berberine may lower your blood sugar levels, and when paired with other glucose-lowering drugs, you could be at risk for hypoglycemia.
• Robitussin DM (dextromethorphan): Berberine could reduce your body’s ability to quickly break down dextromethorphan.
• Blood thinners (anticoagulants or antiplatelets): Given that berberine may slow down blood clotting, taking it along with blood thinners may exacerbate this process, increasing risk for bleeding and bruising.

Berberine could cause some gastrointestinal problems like diarrhea, cramping, or constipation. It is unsafe to use on newborns, and people who are pregnant or breastfeeding should avoid using this supplement.

Alpha-Lipoic Acid

Alpha-lipoic acid is a compound found inside each cell in the human body. It converts your glucose into energy by way of oxygen. This is called aerobic metabolism.

A 2012 study surveyed 38 people with type 2 diabetes who were put on daily 300, 600, 900, and 1,200 mg treatments of alpha-lipoic acid over six months. After treatment, the participants were monitored for their glucose status and oxidative biomarkers. The researchers found that these individuals’ fasting blood sugar levels and A1C decreased in measure with dosage increase.

Another 2011 review looking at how alpha-lipoic acid has been used to treat diabetes cited the compound’s impact on glucose levels, but focused more on its role as an antioxidant. Most of the available research has focused on that element of the supplement’s effectiveness.

A 2019 review examined a series of studies on the effectiveness of alpha-lipoic acid. The analysis offers a mixed bag—while some of the research was encouraging, others showed alpha-lipoic acid to be no more effective than placebos administered to participants. Overall, the authors suggested that while some of the research is encouraging, more studies with larger sample sizes need to be conducted to paint a more conclusive picture of this supplement.

How to Use Alpha-Lipoic Acid

Dosage of alpha-lipoic acid greatly varies. One study cited a dosage range from 600 mg to as high as 1,200 mg daily before eating.

Precautions

Alpha-lipoic acid can interact with some medications, including diabetes medications, chemotherapy medications, thyroid medications, and vitamin B1. As always, consult with your healthcare provider before adding any new supplement to your treatment regimen.

Probiotics

Probiotics are healthy bacteria found in certain foods that may help reduce blood sugar in people with diabetes. These "good" bacteria help support the natural environment of bacteria and fungi in the gut and, by doing so, aid in the digestion of carbohydrates that might otherwise give rise to hyperglycemia.

In addition to probiotic foods, there are probiotic supplements that can deliver these "good" bacteria to your body in a large concentrated dose.

A 2021 review of studies involving 20 randomized controlled trials and 2,972participants concluded that probiotic supplements were especially good in managing blood surgery in people with gestational diabetes, the type that can develop during pregnancy.

How to Use Probiotics

In addition supplement, probiotics are found in fermented foods like:

• Yogurt
• Kefir
• Sauerkraut
• Kimchi
• Pickles

When taken as a supplement, a daily dose of between10 to 20 billion CFU(colony-forming units) is considered safe and effective in maintaining a healthy balance of bacteria in your gut.

Precautions

Probiotics are generally considered safe but may cause side effects in some, including mild stomach upset, diarrhea, gas, and bloating. These tend to occur during the first few days of treatment but will generally subside as your body gets used to the supplements.

Nigella

Nigella sativa, also known as black cumin seed or simply black seed, is a naturopathic remedy thought to have blood sugar-lowering properties. Proponents suggest that it can treat a wide range of medical conditions, including high blood pressure, skin infections, diarrhea, liver disease, and others.

A 2019 review of studies suggested that Nigella is able to lower blood sugar in people with type 2 diabetes by increasing not only insulin sensitivity but overall insulin levels. The compound thought to effect these changes is an essential oil known asthymoquinone. Despite the positive findings, the quality of the seven reviewed studies was poor.

How to Use Nigella

Nigella supplements are sold online and in many drugstores and supplement shops. The manufacturer's recommended daily intake is between 1,000 and 2,000 mg per day taken in a single dose. The supplement is typically sold as a gel cap containing black cumin seed oil.

Precautions

Nigella sativa is generally regarded as safe when used for culinary purposes or taken as a daily supplement. Even so, it can cause stomach upset, gas, bloating. nausea, vomiting, or constipation, especially when taken at higher doses.

It can also interact with certain drugs used to treat high blood pressure. If you are being treated for high blood pressure, speak with your healthcare provider before using Nigella in any form.

Zinc

Researchers have long recognized that many people with type 2 diabetes have zinc deficiency, leading some to assume that zinc supplements may help improve blood sugar control.

To date, the evidence of this remains mixed. Although a 2015 review of studies suggested that zinc supplements (ranging from 5 to 50 mg) showed promise in managing blood sugar in people with type 1 and type 2 diabetes, neither the findings nor the quality of the studies were consistent.

Even so, the use of zinc supplements was considered reasonable given the many complications that can arise with zinc deficiency (including vision problems, fatigue, skin changes, and an increased risk of infection).

How to Use Zinc

The recommended daily intake of zinc from all sources is11 mg per day for adult males and 8 mg per day for adult females. Pregnancy and breastfeeding require slightly higher doses (11 mg and 12 mg respectively),

In addition to supplements, excellent food sources of zinc include:

• Oysters
• Red meat
• Fish
• Beans
• Nuts
• Dairy
• Fortified breakfast cereals.
• Whole grains

Precautions

You generally can't "overdose" on zinc because it is readily excreted from the body in urine. Even so, taking high doses all at once may cause side effects like headache, nausea, stomach upset, diarrhea, and vomiting.

Zinc can also interfere with the absorption of nonsteroidal anti-inflammatory drugs (NSAIDs) like Aleve (naproxen) and Indocin (indomethacin), making these painkillers less effective.