When people think about obesity and type 2 diabetes, they usually focus on diet, exercise, insulin, or blood sugar. But researchers are continuing to uncover deeper metabolic pathways that may help explain why some people struggle more than others with weight gain, insulin resistance, and poor glucose control.

One area of growing interest is an enzyme called NNMT, short for nicotinamide N-methyltransferase. While the name sounds technical, its role may be very important in understanding how the body handles energy, stores fat, and regulates blood sugar.

What Is NNMT?

NNMT is an enzyme involved in how the body processes nicotinamide, a form of vitamin B3 that plays a role in the production of NAD+. NAD+ is essential for many metabolic functions, including how the body creates and uses energy.

Researchers believe NNMT may influence how efficiently the body burns fuel, stores fat, and responds to insulin. In recent years, elevated NNMT activity has been linked to both obesity and type 2 diabetes, making it an increasingly important target in metabolic research.

How NNMT May Be Connected to Weight Gain

The research reviewed in the paper found that NNMT activity tends to be higher in people with obesity and in animal models prone to weight gain. Higher NNMT expression has also been observed in white adipose tissue, which is the body fat most commonly associated with excess weight and metabolic disease.

Why does that matter?

Because NNMT may affect how much energy the body burns. Studies discussed in the review showed that when NNMT was reduced or blocked, energy expenditure increased. In animal research, this was associated with:

• reduced body weight

• lower white fat mass

• improved metabolic efficiency

In simple terms, when NNMT activity was lowered, the body appeared to burn more energy and store less fat.

The Link Between NNMT and Type 2 Diabetes

Type 2 diabetes is closely tied to insulin resistance, poor glucose regulation, and abnormal fat metabolism. The review found that NNMT may be involved in all of these.

Researchers reported that NNMT expression was increased in people with insulin resistance and type 2 diabetes, as well as in diabetic animal models. Elevated levels of NNMT’s metabolic product were also found in blood and urine samples from individuals with diabetes.

More importantly, studies in the paper showed that lowering NNMT activity was associated with improvements in:

• insulin sensitivity

• glucose tolerance

• fasting blood sugar

• liver glucose output

That suggests NNMT may play a direct role in the processes that drive blood sugar imbalance and metabolic dysfunction.

Why the Liver May Be a Big Part of the Story

One of the most interesting findings in the review is that NNMT may help regulate gluconeogenesis, which is the liver’s process of making glucose.

In people with metabolic dysfunction, the liver can sometimes produce too much glucose, contributing to elevated fasting blood sugar. The paper describes research showing that when NNMT was reduced, the liver produced less glucose. When NNMT was increased, glucose production went up.

This is important because it suggests NNMT is not just associated with obesity and diabetes — it may also be helping drive some of the metabolic patterns seen in those conditions.

Could NNMT Become a Future Treatment Target?

Possibly. According to the review, NNMT is emerging as a promising therapeutic target for obesity and type 2 diabetes. Researchers have already studied experimental approaches designed to inhibit NNMT, including both oligonucleotide therapies and small-molecule inhibitors. In preclinical research, some of these approaches showed encouraging results, including reductions in body weight, better insulin sensitivity, and improved glucose control.

However, there is an important limitation: clinical trials in humans have not yet been reported in this review. That means the science is promising, but it is still evolving. NNMT is an exciting research target, not yet a standard medical treatment.

What This Means for Patients Right Now

NNMT research reinforces a bigger truth in metabolic health: weight gain, insulin resistance, and blood sugar problems are not always just about willpower. They are often tied to deeper biochemical processes happening in the body.

For patients dealing with:

• stubborn weight gain

• insulin resistance

• metabolic syndrome

• prediabetes

• type 2 diabetes

• fatigue and poor metabolic function

it may be helpful to look beyond the scale and take a more complete view of metabolism.

At Boris Bobyr NP, we understand that metabolic health is complex. A personalized approach may include looking at hormones, body composition, lifestyle factors, insulin resistance, nutrition, and other drivers that can affect long-term health and weight management.

Final Thoughts

NNMT is one of several emerging metabolic pathways being studied in relation to obesity and type 2 diabetes. The research suggests that higher NNMT activity may be associated with increased fat storage, lower energy expenditure, insulin resistance, and elevated blood sugar. Early findings also suggest that inhibiting NNMT could one day become part of future treatment strategies.

While more human research is needed, this science adds to a growing body of evidence that metabolic health is far more complex than calories alone. Understanding the underlying biology may help us create better, more personalized approaches to prevention and care.