Diabetes is a disease that occurs when insulin, a hormone that regulates your blood sugar level, is not produced in sufficient amount by the pancreas or when the body is not able to use the insulin produced. High blood glucose is the hallmark of uncontrolled diabetes. 
There are two types of diabetes – type 1 diabetes and type 2 diabetes. Lack of insulin production causes type 1 diabetes which is also known as Insulin-dependent diabetes as it requires daily administration of insulin. Type 2 diabetes is non-insulin dependent diabetes, which is the outcome of the body’s ineffective use of insulin. Majority of the people across the world have type 2 diabetes. 
Do you know that more than 30 million have been diagnosed with diabetes in India; the actual estimate is closer to 40 million.
On the other hand, Alzheimer’s disease (AD) is a degenerative and a progressive disease of the brain, the exact cause of which is still unknown. AD is a common form of dementia and accounts for 60-80% of the cases of dementia. Even though diabetes and AD appear to be two distinct diseases; recent scientific evidence indicates that both the conditions are linked as they involve an impaired balance of glucose in the body and altered brain function.[3-5]
The link between diabetes and AD
There is some connection between these two diseases. In fact, AD was thought to be type 3 diabetes.  Patients with type 2 diabetes mellitus (T2DM) are at a higher risk of getting AD.
Research says hyperglycemia and insulin resistance in the brain might be the common thread that links both of these conditions. 
A study has revealed a strong association between both the diseases and showed that 81% of Alzheimer’s cases had T2DM or impaired fasting glucose (IFG).
Although there seems to be a connection between AD and diabetes, diabetes-related dementia has not been reported yet. However, a significant working mechanism related to diabetes-related dementia has been identified. 
AD is a risk factor for T2DM and vice-versa as data shows that these diseases are connected at multiple levels. Recent studies have also revealed common pathogenic mechanisms shared by both the disorders.
Are there any preventive measures for diabetes-related dementia?
- Studies suggest nutrients and natural food components like curcumin and resveratrol were found to be beneficial in the prevention of the disorder.
- Several functional components of food such as vitamin B6, folate, niacin and vitamin B12 were found to be potential candidates in the prevention or treatment of diabetes, hyperglycemia and AD.
- Tannic acid has shown some excellent inhibitory properties in a study and forms a new therapeutic approach in T2DM and AD.
- Additionally, some dietary approaches such as Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) and Dietary Approaches to Stop Hypertension (DASH) diets are said to be effective in the prevention of dementia, but significant research findings are still required.
To sum up, scientists now give you another reason to keep your sugar under control. The risk for dementia increases two-fold in people with diabetes; therefore, one must control blood sugar levels as it might help in lowering the risk of developing AD in the future.
- World Health Organization. Diabetes [Internet]. [updated 2018 Oct 30; cited 2020 Jan 6]. Available from: https://www.who.int/news-room/fact-sheets/detail/diabetes.
- Diabetes.co.uk. Diabetes in India [Internet]. [updated 2019 Jan 15; cited 2020 Jan 6]. Available from: https://www.diabetes.co.uk/global-diabetes/diabetes-in-india.html.
- National Health Portal. World Alzheimer Day 2019 [Internet]. [updated 2019 Sep 19; cited 2020 Jan 6]. Available from: https://www.nhp.gov.in/world-alzheimer-day-2019_pg.
- Kresser Institute. The link between diabetes and Alzheimer’s disease [Internet]. [updated 2018 Mar 26; cited 2020 Jan 6]. Available from: https://kresserinstitute.com/the-link-between-diabetes-and-alzheimers-disease/.
- Akter K, Lanza EA, Martin SA, Myronyuk N, Rua M, Raffa RB. Diabetes mellitus and Alzheimer’s disease: shared pathology and treatment? Br J Clin Pharmacol. 2011 Mar;71(3):365-76. doi: 10.1111/j.1365-2125.2010.03830.x.
- Mostafa M, Yasaman M, Alireza R, Rezvan F, Pouriya D, Alieh A. Diabetes and its predictive role in the incidence of Alzheimer’s disease. Med Sci. 2019 Jan-Feb; 23(95)
- Lee HJ, Seo HI, Cha HY, Yang YJ, Kwon SH, Yang SJ. Diabetes and Alzheimer’s disease: mechanisms and nutritional aspects. Clin Nutr Res. 2018 Oct;7(4):229-40. doi: 10.7762/cnr.2018.7.4.229. Epub 2018 Oct 23
- Vieira MNN, Lima-Filho RAS, De Felice FG. Connecting Alzheimer’s disease to diabetes: underlying mechanisms and potential therapeutic targets. Neuropharmacology. 2018 Jul 1;136(Pt B):160-171. doi: 10.1016/j.neuropharm.2017.11.014. Epub 2017 Nov 10
- Turkan F, Taslimi P, Saltan FZ. Tannic acid as a natural antioxidant compound: discovery of a potent metabolic enzyme inhibitor for a new therapeutic approach in diabetes and Alzheimer’s disease. J Biochem Mol Toxicol. 2019 Aug;33(8):e22340. doi: 10.1002/jbt.22340. Epub 2019 Apr 11.
- Zardoui A, Pourmennati B, Darvishi A. Alzheimer’s disease and diabetes: diffusion tensor imaging as a probable diagnostic measure. J Neurol Neurosci. 2016 May 27;7(3):111. 10.21767/2171-6625.1000111