The incidence of dementia continues to rise and is expected to steepen as the Boomer Generation moves into their golden years. Interesting to note is that Type II diabetes is also 10 times more common in those over age 65 as compared to 45 year olds. (1)
Recent research has begun to show links between dementia and common metabolic disorders such as Type II diabetes. In other words, there are similar mechanisms at work in each disease.
For example, inflammation, abnormal insulin signaling, and mitochondrial dysfunction have all been shown to exist in in both disorders (2,3). For some time, it has been know that diabetics are at increased risk for Alzheimers. (4)
It is now felt that the low grade systemic inflammation, often occurring without symptoms, leads to decreased responsiveness to normal insulin levels resulting in progressive deterioration of overall health and cognitive decline.
Important to recognize is that much of this “silent” and low grade inflammation can be prevented by adopting better life-style and dietary habits. It is currently estimated that up to 70% of the current population is overweight and that these individuals, especially those with a BMI over 30, have a 20 x risk of insulin resistance, Type II diabetes, and all of the other health-related consequences. (5) A 5’4″ woman weighing 175lbs, and a 5’10” man weighing 210 lbs. each have a BMI of over 30.
People with Type II diabetes are a time bomb waiting to explode. Consider the following:
- The risk of dementia is increased 50% (6)
- Diabetes accounts for at least 40% of all cases of kidney failure and 25% of all kidney transplants. (1)
- Death from heart attack and stroke is between 2-5 times higher as compared to those without Type II diabetes. (4)
- Life span is reduced by 11 years for those diagnosed with diabetes at age 40. (7)
- 50% of diabetics have a loss of protective sensation leading to an increased risk of ulceration, severe joint degeneration, and even amputation. (4)
What is even more alarming is that up to 50% of Type II diabetics remain undiagnosed, and that the problem even begins WAY before a persons blood sugar is elevated.
Up to 40% of the population is considered to be “pre-diabetic”, a condition characterized by blood sugar and Hb1AC levels that are higher than normal, but not yet in the diabetic range. Many times these people are told they are “normal” when they are not. Many systems in our body function with a large “reserve system”, and maintaining blood sugar levels is one of those. As an example, one must lose close to 90% of the cells that produce insulin for abnormalities in blood sugar to be seen. (8) Tests such as a 2-hour glucose challenge, with measurement of both blood sugar as well as insulin levels can detect these early abnormalities but they are rarely performed.
Interestingly, when performing a 2-hour glucose challenge, significant hypoglycemia (lowering of blood sugar) is often seen because of an abnormal insulin response to a sugar challenge. Recently, hypoglycemic episodes have also been shown to be associated with a 2 times risk of dementia in elderly subjects. (9)
Is low vitamin D putting you at risk for diabetes and dementia?
Vitamin D deficiency remains today’s hidden epidemic. I continue to be amazed at how many people never have their levels assessed, and even if taking supplements, rarely take an adequate amount.
A fairly recent study has show that the 41% of the population suffers from a deficit in Vitamin D. This is much higher in African Americans and Hispanics. (10)
Patients with low vitamin D levels have a 2-fold risk of dementia (11) People with newly diagnosed Type II diabetes have lower Vitamin D levels compared to others. Individuals with normal levels have a much less risk of Type II diabetes. (12,13) These studies, and others, have shown that adequate Vitamin D helps to reduce systemic inflammation, improve insulin sensitivity, as well as to facilitate more normal insulin production in those whose secretion is impaired.
Abnormal insulin signaling and blood sugar dys-regulation (even in the absence of detectable diabetes) may even explain a portion of people suffering with chronic pain.
Studies have shown that increased blood sugar leads to a reduced threshold for experiencing pain. (14) This means that body tissues can become hyper sensitized. But, such sensitization can even occur with transient elevations of blood sugar and a fasting level that is still normal. (15) Elevated insulin, by itself, even in the absence abnormalities on any other testing, has also been shown to reduce pain thresholds. (8)
Once more, the interconnectedness of how various systems are tied together is illustrated when it is recognized that low vitamin D is also associated with 2 times greater risk of experiencing chronic pain. (16) Chronic pain is associated with depression and depression is also much more common in those with low Vitamin D levels. (17) Depressed patients are also at a greater risk of suffering dementia. (18)
The first step to minimizing future risks is to get your metabolism under control now.
The field of metabolism, especially as it applies to blood sugar regulation, dementia, pain, etc continues to evolve. But, what is clear, is that these disease processes begin long before symptoms develop, and that symptoms can develop long before any clinical abnormalities become apparent. This is especially true for abnormal insulin signaling and low levels of systemic inflammation.
It is also important to recognize, that while the medications used for diabetes will help to control blood sugar, they do nothing to control the underlying causes of systemic inflammation. The best way to do this is with diet, exercise, and the appropriate use of nutrient supplements, when indicated.
I became more interested in this topic as I was preparing a lecture on diabetic nerve disease. It has changed my approach to patients with chronic or recurring pain and I now recommend, among other things, a 2-hour glucose challenge test with insulin measurements in these individuals. For years, I have been checking Vitamin D levels (with a blood test for 25-OH Vit d) and will continue to do so.
There is much more to this topic that I have written about here. The body is complex and our health, or disease states, are often determined by many inter-related factors.
Going beyond a disease specific approach and looking for the unique subtleties in each individual will lead to care that is personalized, effective, and preventative.
- J Clin Investigation, Vol. 115, June 2005
- Diabetes, 2014, July;63(7)
- Front Endocrinol (Lausanne) 2014 July 8, 5(110)
- American Diabetes Association. www.diabetes.org
- J of Cardiovasc Risk, 2003(10)
- Alzheimers Disease International, 2014
- World J. Gastroenterol. 2007 January 14; 13(2)
- Nutr Res. 2011 Jan;31(1)
- J Periph Nerv Syst 2004;9
- Ann Int Med, 2010.
- Proceedings of the Nutrition Society, 2012.
- Metabolic Syndrome and Related Disorders, 2005;3
- Low vitamin D and the risk of developing chronic widespread pain: results from the European Male Ageing Study, Paul McCabe et al., Rheumatology 2014.
- Archives of Internal Medicine, Vol. 171. No. 20, Nov. 14, 2011.