Young people nowadays give in to the pressure of some realities and often try to "solve" their problems by putting up with their discomfort. But when there is an abnormality in the body, it is actually a wake-up call. For example, diabetes, one of the most common chronic diseases in life, is slowly becoming more prevalent at a younger age. So what should young people learn to do to check themselves?

Diabetes is a group of metabolic diseases characterised by hyperglycaemia. Hyperglycaemia is caused by a defect in insulin secretion or impairment of its biological action, or a combination of both. Prolonged hyperglycaemia leads to chronic damage and dysfunction of various tissues, especially the eyes, kidneys, heart, blood vessels and nerves.

There are more than 100 complications associated with diabetes, and the slightest mistake can lead to blindness or kidney failure or even heart attack, stroke and amputation of a lower limb - a series of dire consequences that we cannot afford, no matter which one.

Research on diabetes has been of great interest and in June 2023, an article published in Clinical Nutrition ESPEN, Osaka University, Japan, showed that oral administration of 250 mg of NMN per day for approximately three months increased serum insulin levels five-fold. 

The researchers went on to show that this supplementation regimen significantly increased plasma NAD+ levels after one month and gradually decreased over the following two months of NMN. Taking NMN also increased NMN levels in plasma (the non-cellular liquid component of blood) for circulation to cells and tissues throughout the body. The results of the study confirm that NMN supplementation can increase NAD+ levels and suggest that NMN can increase insulin levels, a marker of metabolic health, which helps the body use glucose for energy.

NMN boosts insulin and NAD+ levels

To better understand the effects of NMN on human metabolism, scientists measured insulin levels in serum (plasma with clotting factors removed). The initial average blood insulin concentration was 6.95 µIU/mL, which increased significantly fivefold to 39.2 µIU/mL after two months of NMN. in the third month of NMN supplementation, insulin levels gradually decreased to 28.1 µIU/mL. insulin levels were measured after lunch, and elevated blood glucose levels after eating stimulated higher blood insulin levels. The results showed that two months of NMN supplementation increased postprandial insulin levels to help the body use glucose for energy.

As with most studies of the effects of NMN on humans, the Japanese team sought to find out how NMN affects NAD+ levels. They measured plasma NAD+ levels one, two and three months after taking NMN and one month after stopping NMN supplementation. They found that, on average, NMN increased NAD+ levels more than fivefold after 1 month and gradually decreased after 2 and 3 months. NAD+ concentrations were significant at 1, 2 and 3 months on NMN. One month after stopping NMN, NAD+ levels decreased to near initial concentrations. These findings confirm that NMN increases NAD+ in the blood and suggest that higher NAD+ levels will gradually decrease over the months of supplementation.

As previous studies had shown that NMN administration in whole blood containing plasma, blood cells and clotting factors did not increase whole blood NMN concentrations, Ochiyama and colleagues measured NMN concentrations in plasma without blood cells. Interestingly, they found that NMN levels more than doubled throughout the NMN supplementation regimen and fell back to baseline levels one month after supplementation was stopped. Importantly, the values of NMN concentrations were widely distributed among the 11 study participants, suggesting a wide variation in the ability of individuals to absorb NMN. Blood cells had a significant effect in measuring NMN concentrations, and previous studies have shown that NMN administration does not increase NMN concentrations in whole blood. NMN concentrations in plasma without blood cells are higher than those in whole blood, which may mean that blood cells rapidly metabolise most of the blood NMN.

Clinical research supports NMN for diabetes prevention

Studies have confirmed that supplementation with moderate amounts of NMN (250 mg/day) significantly increases blood levels of NAD+ and gradually decreases over months of continued supplementation. Interestingly, NMN also increased postprandial (after-meal) insulin levels. Since a previous study showed that NMN also increased muscle insulin sensitivity in pre-diabetic women, producing more insulin with NMN may be a way to prevent diabetes.

Summary

Four main effects of NMN on diabetes

1. Regulation of insulin secretion

Both diabetes type 1 and type 2 are associated with inadequate insulin secretion or abnormal insulin receptor function. And by increasing NAD+ levels in the body, NMN can help regulate insulin secretion and enhance insulin sensitivity, thereby reducing spikes and fluctuations in blood glucose values. This means that NMN may help to improve insulin resistance and blood glucose control in diabetic patients.

2. Reduces oxidative stress

Diabetic patients often suffer from oxidative stress, and NMN has good antioxidant capacity to reduce free radical damage to the body, reduce inflammatory responses and help prevent cellular lipid peroxidation. This means that NMN can protect patients from further damage caused by oxidative stress, while reducing symptoms of oxidative stress in diabetic patients.

3. Promotes glucose uptake and utilisation

Cellular energy metabolism requires a large supply of ATP, and NMN promotes the production of NAD+ in cells, helping them to take up and utilise glucose more quickly and efficiently, thereby improving the body's metabolic rate and exercise performance. This is valuable for people with diabetes, who tend to have relatively low metabolic rates, resulting in inadequate energy expenditure and a tendency to develop obesity and other related problems.

4. Improves blood lipid levels

Diabetic patients often suffer from abnormal lipid metabolism and NMN can lower plasma triglyceride and total cholesterol levels while increasing high-density lipoprotein cholesterol (HDL-C) levels. By modulating these lipid indicators, NMN may help to reduce the risk of cardiovascular disease in diabetic patients.

In summary, NMN may have a variety of benefits for diabetic patients, including improving insulin secretion, reducing oxidative stress, promoting glucose utilization, and improving lipid markers. However, it should be noted that NMN is still in the research stage and its exact efficacy in the treatment of diabetes is yet to be confirmed.