About 25 to 40 percent of men with type 2 diabetes have clinically low testosterone, making it one of the most common hormonal complications of the disease. The two conditions feed each other: high blood sugar suppresses testosterone production, while low testosterone reduces muscle mass and makes it harder for your body to absorb glucose. Breaking that cycle requires targeting both problems at once, and there are several effective ways to do it.
Why Diabetes Lowers Testosterone
The connection runs through a signaling problem in the brain. In most men with type 2 diabetes who have low testosterone, the issue isn’t in the testes themselves. Instead, the pituitary gland stops sending the right hormonal signals (LH and FSH) to trigger testosterone production. This pattern, called hypogonadotropic hypogonadism, accounts for roughly 25 percent of men with type 2 diabetes. Another 4 percent have a different form where the testes themselves are underperforming despite receiving the correct signals.
Insulin resistance, excess body fat, and chronic inflammation all contribute to this brain-level suppression. The result is a vicious cycle: low testosterone leads to less muscle, which worsens blood sugar control, which further suppresses testosterone. Anything that improves insulin sensitivity or reduces body fat can help reverse the process.
Lose at Least 15 Percent of Your Body Weight
Weight loss is the single most powerful natural lever for raising testosterone in men with diabetes, but modest weight loss isn’t enough. Research from the Cleveland Clinic found that men who lost more than 15 percent of their body weight saw total testosterone rise by an average of 210 ng/dL, compared to just 86 ng/dL in men who lost less than that threshold. For a 220-pound man, 15 percent means losing about 33 pounds.
That’s a significant amount, and it’s one reason bariatric surgery has shown strong results for testosterone recovery in men with type 2 diabetes. Five years after surgery, free testosterone levels remained elevated. But you don’t necessarily need surgery to reach that target. Sustained dietary changes, exercise, and newer diabetes medications can all contribute to that degree of weight loss over time.
Strength Training and Aerobic Exercise
Resistance training directly stimulates testosterone production in muscle tissue and improves insulin sensitivity at the same time. Animal studies on type 2 diabetes models show that consistent strength training, performed three days per week on alternating days, increases levels of active testosterone in muscle and improves glucose metabolism. Each session doesn’t need to be long or complicated. Multiple sets of compound movements (squats, deadlifts, rows, presses) at moderate to high intensity, with short rest periods, are the type of training most consistently linked to hormonal benefits.
Aerobic exercise matters too, primarily because it accelerates fat loss and improves blood sugar control. Combining both forms of exercise gives you the best results for both testosterone and diabetes management. If you’re starting from a sedentary baseline, even two to three sessions per week of each type can make a measurable difference within a few months.
Get Blood Sugar Under Control
Hyperglycemia directly suppresses testosterone production. Improving your HbA1c, the measure of average blood sugar over two to three months, can raise testosterone levels on its own. This creates a positive feedback loop: better blood sugar means more testosterone, which means more muscle mass, which means better blood sugar.
One nuance worth knowing: metformin, the most commonly prescribed diabetes drug, may actually lower testosterone slightly. A study of men with type 2 diabetes on insulin found that three months of metformin therapy reduced both total and bioavailable testosterone, and it appeared to counteract the testosterone increase that normally accompanies improved blood sugar. This doesn’t mean you should stop metformin. Its benefits for blood sugar and overall health are well established. But it’s worth discussing with your doctor if you’re dealing with both conditions.
GLP-1 Medications Show Promise
The newer class of diabetes and weight loss drugs, GLP-1 receptor agonists like semaglutide and liraglutide, appear to raise testosterone levels in men. A meta-analysis of four studies found that GLP-1 medications significantly increased both total testosterone and bioavailable testosterone while also lowering HbA1c. The testosterone increase is likely driven by the combination of weight loss and improved blood sugar control these drugs provide.
If you’re already on one of these medications for diabetes or weight management, the testosterone benefit is a meaningful bonus. If you’re considering treatment options and low testosterone is a concern, this is worth raising with your prescriber.
Treat Sleep Apnea
Obstructive sleep apnea is extremely common in men with type 2 diabetes and is an independent cause of low testosterone. The mechanism is straightforward: repeated oxygen drops during the night, combined with fragmented sleep and reduced sleep efficiency, suppress the pituitary signals that drive testosterone production. On top of that direct effect, sleep apnea worsens insulin resistance and promotes weight gain, both of which further lower testosterone.
If you snore heavily, wake up tired despite sleeping enough hours, or your partner has noticed you stop breathing at night, getting a sleep study is one of the highest-impact steps you can take. Treating sleep apnea with a CPAP machine or other interventions can improve testosterone, blood sugar, and energy levels simultaneously.
Zinc and Nutritional Support
Zinc plays a well-documented role in testosterone production and glucose metabolism. Men with diabetes are more likely to be zinc deficient, and supplementation can help on both fronts. Research suggests that around 20 mg per day of zinc may be the sweet spot for improving metabolic parameters in people with diabetes, though studies have used doses ranging from 7.5 to 660 mg per day depending on the form of zinc used.
Vitamin D deficiency is also linked to both low testosterone and poor blood sugar control. If you haven’t had your levels checked, it’s a simple blood test. Getting adequate vitamin D through sun exposure, food, or supplementation supports testosterone production and insulin sensitivity. A diet rich in healthy fats, lean protein, and whole foods provides the broader nutritional foundation your body needs for hormone production.
When Testosterone Replacement Therapy Makes Sense
The clinical threshold for diagnosing low testosterone is a total level below 264 ng/dL, based on the Endocrine Society’s standardized reference range. If your levels are consistently below this number and you have symptoms like fatigue, low libido, reduced muscle mass, or depressed mood, testosterone replacement therapy becomes a consideration.
Data from a large audit of men with both low testosterone and type 2 diabetes showed that TRT was associated with progressive HbA1c improvements over three years. At six months, average HbA1c dropped from about 8.6% to 8.1%. By three years, it had fallen to roughly 6.9%, which is a substantial improvement.
However, the Endocrine Society specifically recommends against using testosterone therapy as a primary tool for improving blood sugar control. The guideline reflects the fact that lifestyle changes and diabetes management should come first. TRT is appropriate when low testosterone persists despite those efforts and is causing symptoms that affect your quality of life. It’s not a substitute for weight loss, exercise, and blood sugar management, but when combined with those foundations, it can close the remaining gap for men who need it.