The body requires thiamine to convert carbohydrates into glucose, which is the primary source of energy for the human body. Since thiamine is essential for glucose metabolism, it is believed that low levels can impact glucose control in the body. Hence, the benefits of thiamine for diabetics have been extensively studied.

What Is Thiamine?

Thiamine, also known as vitamin B1, aids in carbohydrate utilization [1]. It’s needed for glucose metabolism in the nervous system, muscles, and heart [2].

Vitamins are classified by the medium in which they dissolve. Some are soluble in water, others in fat. The bloodstream carries water-soluble vitamins. What the body doesn’t need is expelled in the urine.

Because thiamine is a water-soluble vitamin that is quickly excreted from the body, a steady dietary intake is required to keep your blood levels regular [3].

Thiamine supplementation is available in two forms. Firstly, it is sold as an oral supplement you can grab off the drug store’s shelf without a prescription. Secondly, it also exists in an injectable form that can only be administered by a trained healthcare professional [4].

What foods contain thiamine?

Other than supplements, you can also source thiamine from foods such as: 

  • Peas
  • Beans
  • Nuts
  • Meat
  • Whole grains
  • Cereals
  • Romaine lettuce
  • Aubergine
  • Cabbage
  • Spinach
  • Brussels sprouts
  • Tomatoes
  • Kale
  • Carrots
  • Onions
  • Broccoli [5]

Thiamine is required to convert carbohydrates into energy and other body products.

What is benfotiamine?

Benfotiamine is a lab-made version of vitamin B1. The body absorbs benfotiamine better compared to thiamine. Currently, researchers are testing it on diabetic nerve damage, Alzheimer’s disease, and alcoholism.

The early stages of research into the benefits of benfotiamine have shown promising results. Various brands have claimed that benfotiamine can help with Alzheimer’s, arthritis, and other conditions. Unfortunately, more proof is needed to back up these claims, so do take them with a grain of salt in the meanwhile! [6].

Does Thiamine Lower Blood Sugar In Diabetics? 

Thiamine is a water-soluble vitamin involved in carbohydrates metabolism. Glucose metabolism requires the B vitamin thiamine.

In one study, one month of thiamine treatment reduced blood glucose levels in type 2 diabetics [7]. Additionally, two other studies revealed that after 45 days of thiamine treatment, glycosylated hemoglobin (HbA1c) levels decreased significantly in participants [8,9]. HbA1c tests indicate the amount of glucose and act as an overall marker of your blood glucose control over a period of two to three months. 

In short, from the results of several studies, thiamine can indeed lower blood sugar levels in diabetics.

Is Thiamine Good For Diabetics?

Other than lowering blood glucose levels, thiamine has a few other benefits tucked up its sleeve! In fact, Warwick University researchers believe that this low-cost supplement could benefit the majority of type 1 diabetics and type 2 diabetics. Furthermore, 70% to 90% of diabetic patients have thiamine deficiency.

According to Alam et al.(2012), a subsequent Pakistani study used 300 mg thiamine per day for three months to replicate the findings. [10] From this study, low thiamine levels in diabetics were due to increased kidney excretion, rather than low dietary intake.  Hence, Alam advises type 2 diabetics to take 300 mg of thiamine daily to keep their thiamine levels up. The study found no adverse side effects from this treatment.

So how can thiamine benefit diabetics? Research has discovered that it can help with the following diabetic complications. 

Diabetic Nephropathy

Supplementing with thiamine may help prevent diabetic nephropathy, a potentially fatal complication of diabetes associated with an increased risk of heart disease and death [9].

In diabetic patients, thiamine treatment resulted in the improvement of early diabetic renal disease.

Dr. Rabbani of the Warwick Medical Centre published a double-blind clinical trial in 2009 showing improvement of early diabetic renal disease in diabetic patients receiving high-dose thiamine [10]. This was a 12-week pilot study involving 40 diabetics of type two.

After three months of treatment with a high dose (300mg) of thiamine taken orally once daily, one-third of the study’s patients had normal urinary albumin excretion. According to experts, thiamine protects kidney cells from the dangerous effects of diabetes-related high blood sugar levels.

Diabetic Cardiomyopathy

Diabetic cardiomyopathy, or the disease of heart muscles, can lead to heart failure which increases the risk of death. In diabetic mice, thiamine improved both functional and survival recovery of infarcted hearts. Cardiomyocyte apoptosis, or the cell death of heart tissues, was also reduced [11].

Because these studies were carried out in animal models, further human studies are warranted to establish the efficacy of thiamine in preventing diabetic cardiomyopathy.

Diabetic Neuropathy

Diabetic polyneuropathy is a common complication of diabetes, affecting 10% of people in the United States and Canada. Due to high blood glucose levels, the motor and sensory nerves that lead into the arms, legs, and feet are damaged.

Thiamine has been demonstrated to alleviate pain and improve nerve function in patients with diabetic neuropathy [12].

Diabetic Retinopathy

Diabetic retinopathy, or damage to the retina of the eye, is one of the most severe complications of diabetes which causes blindness. Thiamine reduces the risk of blindness by regulating the glucose in retinal cells (eye cells) [13].


Do Diabetics Need To Take Thiamine? 

Diabetes patients have lower thiamine levels due to increased kidney thiamine excretion, 25 times greater than usual. This causes acute thiamine deficiency, also known as beriberi, a nervous system disorder.

Diabetes damages the body’s small blood vessels, causing amputation. When the blood vessels supplying the kidneys are affected, the kidneys become unable to function correctly, resulting in protein loss into the urine. Albumin is one of them.

The study, led by P. J. Thornalley of the University of Essex in the UK, included 48 Type 2 diabetics, 26 Type 1 diabetics, and a total of 20 healthy individuals. The study found that Type 2 diabetics and Type 1 had 75% and 76% lower thiamine levels in their blood plasma than healthy controls [14].

Diabetes patients excrete thiamine at a much higher rate

Thornalley also investigated the body’s thiamine metabolism and discovered that Type 1 diabetics and Type 2 diabetics excreted thiamine 24 and 16 times faster, respectively than people without diabetes [15]. After determining that people with diabetes may require higher thiamine doses, the researchers discovered additional studies demonstrating that high thiamine doses can prevent small-blood-vessel damage.

Because diabetics are at higher risk of thiamine deficiency, and clinical studies have proven the various benefits of thiamine supplementation in diabetes, you may wish to commence this supplement (after consulting your doctor, of course)! 

How Much Thiamine Should A Diabetic Take?

  • For thiamine deficiency: To prevent thiamine deficiency, people with diabetes should take a daily dose of 5 to 30 mg for one month. The severity of the deficiency calls for up to 300 mg per day.
  • For kidney damage: It has been recommended to take 100 mg of thiamine three times daily for three months.
  • For cataracts: It was determined that a daily dietary intake of approximately 10 mg of thiamine was sufficient [17].

What Are The Side Effects Or Precautions Linked To Thiamine Use?

Thiamine side effects [18]

Seek medical attention if you have any of the following symptoms:

  • Swelling of your tongue, lips, face, or throat
  • Difficulty breathing
  • Hives
  • Bloody vomit or vomit that resembles coffee grounds
  • Tarry, bloody, or black stools
  • Chest pain
  • Blue colored lips

The following are examples of less serious side effects:

  • Tenderness or a hard lump may occur where a thiamine injection was given.
  • Feeling restless
  • Nausea
  • Mild rash or itching
  • Feeling warm
  • Sweating
  • A squeezing sensation in your throat

The following is not an exhaustive list of possible adverse reactions; others may occur. Consult your physician for medical advice regarding adverse effects. To report side effects, contact the FDA at 1-800-FDA-1088.

What are the precautions with thiamine treatment?

It’s best to follow your doctor’s orders regarding any dietary or physical restrictions.

Prior to taking this medication

If you have ever experienced an allergic reaction to thiamine, discontinue use.

Additionally, consult your doctor to discuss thiamine use especially if you meet any of the following criteria:

  • you have an allergy to a particular medication or food.
  • you are currently taking another medicine or herbal supplement
  • you have any additional medical problems

Inform your doctor if you have kidney disease and ask to avoid injectable thiamine.

Thiamine in Pregnancy

Thiamine is unlikely to cause harm to an unborn child. During pregnancy, your thiamine requirements may differ from those of a healthy person. If you are pregnant or intend to become pregnant, you should avoid taking thiamine [19].

Thiamine in Lactating Mothers

It is unknown if thiamine is excreted in human milk. Your dose requirements may change while nursing. Take thiamine only after consulting your doctor if you are nursing your child [19].

Bottomline: Thiamine In Diabetes

Diabetes patients are more prone to thiamine deficiency, which can cause hyperglycemia-induced damage. A thiamine supplement can help prevent harmful glucose metabolism products and oxidative stress while improving blood vessel function. Diabetes patients should not be given a long-term replacement, but it may reduce their risk of cardiovascular disease and support nervous system function.

While this is the conclusion drawn from research studies, it’s still best to seek the advice of your healthcare professional before commencing thiamine as your needs may differ from someone else’s!

Disclaimer: This article is only a guide. It does not substitute the advice given by your own healthcare professional. Before making any health-related decision, consult your healthcare professional

Editorial References And Fact-Checking

  • Office of Dietary Supplements – Thiamin. (2022). National Institute of Health. Retrieved August 19, 2022, from
  • Thiamin. (2020, November 14). Mayo Clinic. Retrieved August 19, 2022, from
  • Martel, J. L., Kerndt, C. C., Doshi, H., & Franklin, D. S. (2021). Vitamin B1 (Thiamine). In StatPearls. StatPearls Publishing.
  • Thiamine. (2022). Drugs.Com. Retrieved August 19, 2022, from
  • What Is Benfotiamine? (2022, May 5). Verywell Health. Retrieved August 19, 2022, from
  • González-Ortiz, M., Martínez-Abundis, E., Robles-Cervantes, J. A., Ramírez-Ramírez, V., & Ramos-Zavala, M. G. (2011). Effect of thiamine administration on metabolic profile, cytokines and inflammatory markers in drug-naïve patients with type 2 diabetes. European journal of nutrition, 50(2), 145–149.
  • Nikolić, A., Kacar, A., Lavrnić, D., Basta, I., & Apostolski, S. (2009). Srpski arhiv za celokupno lekarstvo, 137(11-12), 594–600.
  • Luong, K. V., & Nguyen, L. T. (2012). The impact of thiamine treatment in the diabetes mellitus. Journal of clinical medicine research, 4(3), 153–160.
  • Journal of Diabetes and Metabolism. (2022). Effect of High Dose Thiamine Therapy on Risk Factors in Type 2 Diabetics. International Online Medical Council. Retrieved August 19, 2022, from
  • Katare, R., Caporali, A., Emanueli, C., & Madeddu, P. (2010). Benfotiamine improves functional recovery of the infarcted heart via activation of pro-survival G6PD/Akt signaling pathway and modulation of neurohormonal response. Journal of molecular and cellular cardiology, 49(4), 625–638.
  • Stracke, H., Gaus, W., Achenbach, U., Federlin, K., & Bretzel, R. G. (2008). Benfotiamine in diabetic polyneuropathy (BENDIP): results of a randomised, double blind, placebo-controlled clinical study. Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association, 116(10), 600–605.
  • Beltramo, E., Berrone, E., Tarallo, S., & Porta, M. (2009). Different apoptotic responses of human and bovine pericytes to fluctuating glucose levels and protective role of thiamine. Diabetes/metabolism research and reviews, 25(6), 566–576.
  • Thornalley, P. J., Babaei-Jadidi, R., Al Ali, H., Rabbani, N., Antonysunil, A., Larkin, J., Ahmed, A., Rayman, G., & Bodmer, C. W. (2007). High prevalence of low plasma thiamine concentration in diabetes linked to a marker of vascular disease. Diabetologia, 50(10), 2164–2170.
  • Pácal, L., Kuricová, K., & Kaňková, K. (2014). Evidence for altered thiamine metabolism in diabetes: Is there a potential to oppose gluco- and lipotoxicity by rational supplementation?. World journal of diabetes, 5(3), 288–295.
  • WebMD. (2022). THIAMINE (VITAMIN B1): Overview, Uses, Side Effects, Precautions, Interactions, Dosing and Reviews. Retrieved August 19, 2022, from
  • Thiamine Pregnancy and Breastfeeding Warnings. (2022). Drugs.Com. Retrieved August 19, 2022, from,have%20increased%20needs%20for%20thiamine.


  • Dr Faisal Rasheed, M.D.

    Dr Faisal is a certified Medical Doctor currently carrying the role of a Senior Medical Officer in the Orthopaedic Surgery Department of his local hospital. With his vast experience and knowledge in the medical field, Dr Faisal is well-equipped to share educational content that helps readers improve their health and wellness. During his hospital shifts, he diligently cares for and treats patients under him. And during his spare time, he enjoys crafting health and wellness content that inspires readers to make positive changes. LinkedIn


Dr Faisal is a certified Medical Doctor currently carrying the role of a Senior Medical Officer in the Orthopaedic Surgery Department of his local hospital. With his vast experience and knowledge in the medical field, Dr Faisal is well-equipped to share educational content that helps readers improve their health and wellness. During his hospital shifts, he diligently cares for and treats patients under him. And during his spare time, he enjoys crafting health and wellness content that inspires readers to make positive changes. LinkedIn