Curcumin - Part IV: Diabetes Studies
This article is the fourth of a series on the beneficial actions of curcumin. Curcumin is one of the most widely studied natural substances with over 4000 scientific studies documenting its benefits in a wide variety of diseases including diabetes, heart disease, neurodegenerative disease such as Alzheimer’s, cancer, arthritis, skin and oral diseases.1,2 There is ample evidence to recommend its use in diabetes, which is discussed in this article.
What is Diabetes?
There are two main types of diabetes: Type 1 and Type 2. Type 1 diabetes is principally a genetic condition which results from autoimmune damage of the pancreatic cells which produce insulin. It tends to present in childhood and results in lifelong dependence on insulin injections. Type 2 diabetes is far more common. It is mainly seen in the context of a sedentary lifestyle, poor diet and obesity. It is no secret that this condition takes a very heavy toll in the Bahamas, as in most western countries.
How dOes Diabetes Affect Your Health?
Diabetes dramatically increases the risk of cardiovascular disease and leads a two to three fold risk of heart attack and stroke. Among other factors, elevated levels of glucose causes damage to tiny blood vessels and results in widespread complications including neuropathy (nerve damage), retinopathy (eye damage and potentially blindness), kidney damage and failure, and degeneration of brain cells (including Alzheimer’s). In the limbs small vessel damage in conjunction with nerve damage can lead to foot ulcers, infection and eventually to limb amputation. Furthermore, the chronic inflammation seen in the context of diabetes and obesity is also a recognized risk factor for cancer development.
The Rate of Diabetes has Climbed Rapidly
Tragically the prevalence of Type 2 diabetes has increased dramatically over the past 30-40 years. Between 1980 and 2014 there was almost a four fold increase worldwide3 and in some countries, including the Bahamas, the rate of increase is thought to be even higher. This is mainly attributable to the western diet in which staggering increases in the amounts of sugar and other refined carbohydrates are now being consumed, along with a reduction in fiber content and vegetables. In the past Type 2 diabetes was mainly seen in the middle aged and elderly. However changes in our diet are leading to presentation at much younger ages. Diabetes occurring in the youth means that its damaging effects accumulate over a much longer period of time with far greater health consequences.
Curcumin May Help to Prevent Diabetes
As the saying goes, an ounce of prevention is worth a pound of cure. Clearly the most important step in preventing Type 2 diabetes is a change in the diet with dramatically less sugar and other refined carbohydrates (white rice, white bread and pasta etc.) and increase in fiber (multigrain bread, sweet potato etc.) and incorporating a high proportion of green leafy vegetables. In practical terms this means avoiding most fast food options, sugary drinks and excess alcohol. Along with dietary and other lifestyle changes, curcumin has emerged as a powerful ally in the prevention of Type 2 and possibly even Type 1 diabetes. A number of animal studies have shown impressive evidence of a beneficial role of curcumin in preventing diabetes.4-7 However animal studies, although suggestive, are not necessarily translatable into an equal effect in humans.
One large well designed human study was very helpful in confirming a preventative role of curcumin in diabetes.8 It was published in 2012 by the American Diabetic Association‘s journal, Diabetes Care. It compared the response of 120 pre-diabetic patients who were given curcumin daily to 120 matched control subjects. Pre- diabetes is a condition where blood glucose, and more long term indicators of diabetes, such as HbA1c are elevated, but not high enough to be classified as diabetes.
After 9 months, 16% of the group that did not receive curcumin had progressed to outright diabetes, whereas in the group that received curcumin, no one developed diabetes. Moreover, there was statistically significant improvement in a number of metabolic indicators in these patients such as fasting blood glucose, HbA1c and glucose tolerance test by even the third month. In addition, markers for insulin resistance and pancreatic cell function were also improved in the group of patients taking curcumin.
There is also growing evidence that curcumin can prevent the destruction of pancreatic cells and therefore may be able to play a role in preventing Type 1 diabetes.9,10
Curcumin Helps to Control Diabetes and Reduce Complications
Here again a plethora of animal studies have demonstrated use of curcumin supplementation can significantly improve diabetic control.11-14 Dramatic reversal of the blood glucose and other indices were reported in a case study in India as early as 1972.15 A systematic review and meta-analysis of randomized control trials also confirmed these improvements in human subjects.16 One of the trials included in this review demonstrated a significant improvement in blood glucose along with HbA1c and triglyceride levels in a study with 100 human subjects.17
It has also been shown that curcumin can reduce diabetic complications such as neuropathy (nerve damage), cardiac complications, fatty liver disease, kidney disease, retinal damage resulting in vision loss and perhaps even the higher incidence of Alzheimer’s disease seen in diabetics.
Exciting New Developments
Many of the curcumin studies cited above used concentrated tumeric extract or pure curcumin. A number of people choose to use tumeric powder as a means of deriving these benefits. However tumeric powder only contains about 3-4% curcumin and its not very soluble. So although it undoubtedly gives some benefit, its impossible to match the types of response seen in these studies by just adding tumeric powder to the diet unless you consume huge volumes as the Indian case study referenced above: this patient consumed 5g of tumeric per day!
There is currently a great deal of focus on formulating curcumin products which can be easily digested, taken up by the cells and even cross the blood brain barrier so that brain cells can also be targeted. Some important breakthroughs have recently been made in this arena and studies using these newer improved curcumin formulations have shown promising results!
References
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Melo ISV, Santos AFD, Bueno NB. Curcumin or combined curcuminoids are effective in lowering the fasting blood glucose concentrations of individuals with dysglycemia: Systematic review and meta-analysis of randomized controlled trials. Pharmacol Res. 2018 Feb;128:137-144. doi: 10.1016/j.phrs.2017.09.010. Epub 2017 Sep 18.
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