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How cinnamon lowers blood sugar

This popular spice may improve insulin resistance, but the type matters—and it may not be safe for everyone

Key takeaways

  • Diabetes is a medical condition that occurs when your body can’t regulate blood glucose levels. Consistently elevated blood sugar causes health problems, such as heart disease, kidney disease, and nerve damage—particularly in the feet and eyes.

  • Some studies suggest cinnamon can lower blood sugar, improve insulin sensitivity, and lower blood lipid levels. Other studies have found little or no benefit to supplemental cinnamon.

  • Evidence suggests a daily divided dose of 1,000 milligrams to 2,000 milligrams is a good starting point.

  • Ceylon cinnamon is considered safer than the more widely available cassia cinnamon, which can cause liver problems when consumed in large doses.

  • Consult a healthcare provider before adding a cinnamon supplement to your diet.

Diabetes is a medical condition that occurs when your body can’t regulate blood sugar levels. Consistently elevated blood sugar causes health problems, such as heart disease, kidney disease, and nerve damage, particularly in your feet and eyes. Diabetes treatment usually includes medications, such as oral medications, non-insulin injectable medicines, and sometimes insulin, depending on which type of diabetes you have as well as your blood glucose control. On top of that, paying close attention to what you eat and drink is a major part of living with this condition—no matter if you have prediabetes, Type 1, or Type 2 diabetes. Why? Certain foods cause rapid blood sugar spikes, while others affect it more gradually or may even help to lower blood sugar or keep it relatively steady. One of these foods, unexpectedly, is cinnamon.

According to Amy Sapola, Pharm.D., clinical pharmacist at University Hospitals in Cleveland, Ohio, cinnamon may have a modest impact on blood sugar levels. It may also help reduce triglycerides and cholesterol levels. This means this common pantry staple could be a good addition to your diabetes care plan. Here’s what to know.

Does cinnamon lower blood sugar?

Current research suggests that cinnamon may be able to help reduce blood sugar levels and improve insulin sensitivity, says Erin Palinski-Wade, RD, CDCES, New Jersey-based dietitian and author of 2 Day Diabetes Diet.

Several studies have been published demonstrating cinnamon’s positive effects on blood sugar control; a review of studies from 2022, for example, found that eight out of 14 recent clinical trials on humans showed that cinnamon reduced fasting blood sugar and hemoglobin A1C in participants with Type 2 diabetes. A small 2012 study demonstrated similar antidiabetic properties when participants took 1,000 milligrams of cinnamon per day over 12 weeks.

Additionally, some research demonstrates the heart health benefits of cinnamon—a good thing for people with diabetes who are at greater risk of cardiovascular disease. Cinnamon may improve triglyceride and total cholesterol levels, including LDL cholesterol, says Lindsay Malone, MS, RDN, LD, an instructor in the Department of Nutrition at Case Western Reserve University. A 2017 study found significant reductions in blood lipids (including triglycerides and total cholesterol) in people taking supplemental cinnamon.

The study of cinnamon and blood sugar levels involves many variables. Palinski-Wade notes that the dosage, type of cinnamon, and an individual’s response to cinnamon can all affect how effective it is or isn’t for blood sugar management.

On top of that, while much of the evidence is positive, it’s still not overwhelmingly in favor of using cinnamon for glycemic control. Some studies show little to no benefit, with cinnamon having only a modest effect on blood sugar, says Akhil Shenoy, MD, a physician board-certified in endocrinology and medical adviser at Aeroflow Diabetes. Plus, there needs to be more consistency in the research, with formulations varying widely from study to study.

How much cinnamon should I take daily to lower blood sugar?

There’s no official recommendation regarding the amount of cinnamon you should take to lower your blood sugar. Different studies have all used varying amounts, ranging from 120 milligrams to 6,000 milligrams per day, notes Dr. Shenoy. However, several experts suggest starting with a dose between 1,000 milligrams and 2,000 milligrams, or between one half and one full teaspoon, per day.

Experts also recommend splitting up your intake throughout the day, dividing your daily cinnamon into two or three doses, and pairing it with meals containing carbohydrates for the best absorption. Malone suggests:

  • Adding cinnamon to yogurt, coffee, oatmeal, or smoothies
  • Drinking cinnamon tea
  • Sprinkling cinnamon on fresh fruit or sweet potatoes

One important thing to note if you’re considering incorporating more cinnamon into your diet is that there are two main varieties readily sold in stores: 

  1. Cassia: Cassia cinnamon is the most common variety; it contains more of the organic compound cinnamaldehyde (which gives cinnamon its flavor), so it’s stronger and spicier.
  2. Ceylon: Ceylon cinnamon is milder and has less cinnamaldehyde but is generally considered the higher-quality cinnamon—and the type you may want to purchase if you’re choosing to supplement with cinnamon. “Ceylon cinnamon is generally considered the more effective version of cinnamon for blood sugar benefits,” says Palinski-Wade. “This form has a higher antioxidant content and is also lower in coumarin, making it safer for long-term use.”

Coumarin is a naturally occurring compound in cinnamon that can cause liver problems when consumed in high amounts or long-term, says Dr. Sapola, including liver enzyme elevation, liver toxicity, and possibly even liver cancer. She recommends limiting your use of cassia cinnamon to no more than ½ teaspoon per day, especially if you have alcohol-related liver damage, viral hepatitis, or other liver-related conditions. 

If you prefer to take cinnamon capsules instead of adding ground cinnamon to your foods and drinks, Dr. Sapola says it’s important to read the supplement label so you know how much cinnamon is in each capsule. Also, note that cinnamon oil and cinnamon extract do not have the same benefits as a cinnamon supplement and should not be consumed.

How long does it take cinnamon to lower blood sugar?

Studies show that most people will see blood sugar benefits in about four to six weeks. However, Malone says that blood sugar response is highly individualized, and it may make sense to take your blood sugar readings at home to observe any changes more closely. Your healthcare professional can provide medical advice on how often you should check your blood sugar, and whether you should use a continuous glucose monitor (CGM).

Who should avoid cinnamon?

Before taking any supplement or adding a significant amount of an ingredient to your diet, Malone says it’s important to seek medical advice from your healthcare provider first to discuss benefits, risks, and potential interactions with other medications or medical conditions. Dr. Sapola says we don’t know if supplemental cinnamon is safe for pregnant or breastfeeding women. Remember that cassia cinnamon, in particular, can cause liver damage when consumed in high amounts, so anyone with a history of liver problems should be especially cautious when adding cinnamon to their diet.

There are potential drug interactions with cinnamon, too. Malone points to a 2015 case report outlining the interaction between supplemental cinnamon and statin medication for high cholesterol, while Dr. Sapola says coumarin can affect the blood’s ability to clot, which may increase your risk of bleeding if you are taking blood-thinning medication like warfarin. She also recommends caution when taking diabetes medications that lower blood sugar since the combined effects of these medications with cinnamon could result in hypoglycemia (low blood sugar) or dangerously low blood sugar.

Less serious but still notable side effects of increasing your cinnamon intake include mouth sores, per Palinski-Wade, as well as gastrointestinal discomfort and headache, according to Dr. Sapola.

Finally, there have been some recent concerns about the lead content in some cinnamon brands sold in supermarkets. In September 2024, Consumer Reports tested 36 popular brands of ground cinnamon. They found that 12 of them contained potentially unsafe levels of lead, which is a particular safety concern for children and pregnant women but may pose a risk to adults as well.

The bottom line

Some studies suggest that supplemental cinnamon may help reduce fasting blood glucose levels and, as a result, improve insulin sensitivity. However, other studies have shown little to no benefit. There also isn’t much consistency within the published studies: different varieties of cinnamon have been tested in varying amounts, so it’s hard to know if the potential benefits of cinnamon for lowering blood sugar are worth the possible risks, especially since one form of cinnamon (cassia) can be toxic if consumed in large amounts over time.

It’s also worth noting that supplements may play only a small role in helping people manage Type 2 diabetes. In addition to prescribed medication, broader lifestyle changes—like weight loss, regular exercise, monitoring carbohydrate intake, and eating whole, nutrient-dense foods—have a much larger impact on improving overall health for diabetes patients.