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Vitamin C, a Sensible Addition to Diabetes Care Plan
Those who took twice-daily vitamin C supplements had significantly improved fasting and postmeal blood glucose levels
For those managing type 2 diabetes
, eating healthfully, getting regular physical activity every day, losing weight if you’re overweight or obese, and taking medications as prescribed are known to be wise steps for managing diabetes. Now, adding a twice-daily vitamin C supplement
to your self-care routine may be an additional way to keep blood sugar levels in check.
Pla-“C”-bo controlled trial
To study the effects of a vitamin C dietary supplement on blood sugar control in people with type 2 diabetes, researchers randomly selected 70 adults with this condition to take 500 mg metformin—a medication commonly used to manage blood sugar levels in people with diabetes—twice per day, plus:
- 500 mg vitamin C twice daily, or
- a placebo pill (no vitamin C) twice daily.
Study participants provided blood samples, and the researchers tracked indicators of blood sugar control at the beginning and end of the 12-week study, including:
- Vitamin C blood levels
- Fasting blood glucose—a measure of blood sugar levels when a person has not eaten for at least eight hours
- Postmeal blood glucose—a measure of blood sugar levels after a meal
- Hemoglobin A1c (HbA1c)—a measure of long-term blood sugar control (higher HbA1c indicates poor blood glucose control, which can lead to health problems, such as heart disease, kidney failure, and nerve damage)
Compared with people who received metformin plus placebo, those who took twice-daily vitamin C supplements had significantly:
- increased vitamin C blood levels
- improved fasting and postmeal blood glucose levels, and
- decreased HbA1c.
Despite the study’s short duration, these findings point to a simple step—taking a twice-daily vitamin C supplement—that people with diabetes may be able to take to better control their disease.
The A, B, C’s of living well with diabetes
Type 2 diabetes has a genetic component, but even if you have a family history of this disease, you are not destined to get it yourself. And if you already have the condition, managing it well will keep you healthy and reduce your risk of diabetes-related health problems:
- Seek out C, but use care. Consider taking 500 mg of vitamin C twice per day. Adding more vitamin C into your daily routine by taking a supplement or focusing on eating more vitamin C-rich foods is safe for most people, but check with your doctor before making changes to your diabetes self-care routine. This is particularly important if you have kidney disease.
- Focus on food. If you have “C” clearance from your doc, eat more vitamin C-rich foods, such as citrus fruit, peaches, red and green bell peppers, papayas, apricots, pineapple, strawberries, broccoli, kiwi fruit, and sweet potatoes.
- Fight fat. About 80% of people with type 2 diabetes are overweight. If you carry extra pounds, talk to your doctor or dietitian about a sensible weight management plan. Losing just a few pounds is all it takes to improve diabetes control.
- Move more. The risk of diabetes can be lowered by as much as 60%, simply by incorporating moderate daily exercise, such as walking for 30 minutes, and eating less high-fat fare.
- Track progress. If you have diabetes, track your blood sugar levels as recommended by your healthcare provider. You won’t know if you’re improving your health without feedback, and if you’re struggling to keep blood sugar levels in a healthy range, you doctor needs to know this.
(Adv Pharm Sci 2011; doi:10.1155/2011/195271)
Suzanne Dixon, MPH, MS, RD, an author, speaker, and internationally recognized expert in chronic disease prevention, epidemiology, and nutrition, has taught medical, nursing, public health, and alternative medicine coursework. She has delivered over 150 invited lectures to health professionals and consumers and is the creator of a nutrition website acclaimed by the New York Times and Time magazine. Suzanne received her training in epidemiology and nutrition at the University of Michigan, School of Public Health at Ann Arbor.