Weight Loss for Men Over 40: How Hormones, Diet and Exercise Fit Together

Weight loss gets harder for men over 40 because muscle mass gradually declines, daily energy needs fall with it, and busy years usually mean less movement and shorter sleep. Hormones play a part, though usually as one factor among several. The approach that works is steady rather than dramatic: strength training, enough protein, sensible portions, better sleep and a medical assessment where symptoms point to something hormonal.

The scale of the problem is well documented. More than 1 in 2 Australian adults are living with overweight or obesity (Healthdirect, 2024), and for men the risk of weight-related health problems rises once waist circumference reaches 94 cm (Healthdirect, 2024). This guide explains what changes in your body after 40, how testosterone and other hormones fit in, and what the evidence supports.

Why is it harder to lose weight after 40?

The main culprit is muscle. From your 30s onward, men gradually lose muscle mass unless they train to keep it. Muscle burns more energy at rest than fat, so as it declines your body needs fewer kilojoules each day.

Keep eating the way you did at 30 and the surplus gets stored, most visibly around the middle. Abdominal fat is the pattern most strongly linked to health problems, which is why waist measurement tells you more than the bathroom scale alone (Healthdirect, 2024).

Lifestyle changes at this age compound it. Work and family demands usually peak in your 40s, incidental movement drops, and sleep often shortens. Each of those shifts pushes appetite and fat storage in the wrong direction.

How do hormones affect weight after 40?

Testosterone helps maintain muscle mass, and levels peak in adolescence and early adulthood. As men age there may be a small, gradual drop. The widely repeated claim that every man loses a fixed percentage of testosterone each year overstates it: healthy older men in a normal weight range usually do not experience a significant fall (Healthy Male, n.d.).

The relationship often runs the other way. Being overweight or obese is linked to lower testosterone, and weight loss can significantly increase testosterone levels, especially in men with more weight to lose (Healthy Male, n.d.). Extra weight is more often the cause of a low reading than the result of one.

Insulin matters too. Carrying extra weight, particularly around the abdomen, increases the risk of high blood pressure and type 2 diabetes (Healthdirect, 2024). Improving diet and activity helps the body handle blood sugar, and preventing or delaying type 2 diabetes can in turn influence testosterone levels (Healthy Male, n.d.).

Stress rounds out the picture. Long stretches of pressure tend to mean more comfort eating, more alcohol and worse sleep, all of which work against weight control.

Could low testosterone be part of the problem?

Low testosterone can show up as reduced sex drive, lower energy, mood changes, poor sleep, reduced muscle mass and increased body fat (Healthdirect, 2024). Obesity and chronic conditions such as diabetes are themselves causes of low testosterone. That overlap is exactly why testing beats guessing.

Diagnosis needs a blood test, ideally taken in the morning. Levels vary from day to day, so a single low result is not a diagnosis; a second test is needed to confirm it (Healthdirect, 2024). Online quizzes and symptom checkers can help you decide whether to raise it with a doctor, but only a doctor can diagnose a hormonal condition.

Our guide to the 12 key symptoms of low testosterone in men over 40 covers the symptom picture in more detail.

What should men over 40 eat to lose weight?

Skip fad diets. Plans that promise fast results can slow your metabolism, leave you constantly hungry and end in rapid regain (Healthdirect, 2024). The sustainable version is less exciting and far more effective.

Build meals around the five food groups: vegetables of different colours, fruit, whole grains, lean proteins such as fish, poultry, eggs and legumes, and mostly reduced-fat dairy (Healthdirect, 2024). Give protein a place at every meal, since it helps preserve muscle while you lose fat. Cut back on added sugar and keep alcohol modest; it is energy dense and disrupts the sleep your hormones depend on.

Perfection is not required. Losing even 5 to 10 per cent of your body weight can deliver significant health benefits and reduce your risk of complications (Healthdirect, 2024). A dietitian can help you make changes you will actually keep (Healthdirect, 2024).

What exercise works best after 40?

Australian guidelines recommend 150 to 300 minutes of moderate intensity activity a week, or 75 to 150 minutes of vigorous activity, plus muscle strengthening on at least 2 days each week (Better Health Channel, 2023).

The strength work is the part men most often skip, and after 40 it is the part that matters most. Strength training builds muscle, protects bones and joints, supports weight management alongside a healthy diet, and helps control blood pressure, cholesterol and blood sugar (Healthdirect, 2025). Two sessions a week covering the major muscle groups is a solid starting point.

Brisk walking, cycling or swimming takes care of the moderate intensity target. Pick something you can repeat week after week; consistency matters more than intensity at this age. For a structured approach, see The ultimate weight loss strategy for men over 40.

Sleep, stress and your hormones

Short sleep works against you directly. In one study cited by Healthy Male, young men restricted to five hours of sleep a night for one week saw testosterone drop by 10 to 15 per cent (Healthy Male, n.d.). Poor sleep also increases appetite and drains the energy you need to train.

The fixes are simple: a regular bedtime, screens out of the bedroom, caffeine earlier in the day and alcohol kept in check. Our guide to the sleep-performance connection explains the link in more depth.

When should you see a doctor about your weight?

See a doctor if your waist measures 94 cm or more, or if several months of genuine changes to diet and exercise have produced no progress (Healthdirect, 2024). Symptoms of low testosterone are another reason to book in, as is a family history of heart disease or type 2 diabetes.

Medical weight management adds structure: assessment of your health history, blood tests where indicated, a plan built for your circumstances and regular review. Where prescription treatment enters the conversation, doctors prescribe only where it is clinically appropriate for the individual, and diet and activity remain part of any programme. Testosterone therapy is not a weight loss treatment; Healthdirect notes it is unclear whether it benefits older men who have low testosterone but no testicular or pituitary problem (Healthdirect, 2024).

Telehealth makes this easier to fit around work, but it complements your regular GP rather than replacing them. Keep your GP informed about any treatment you start.

How Menova Health approaches it

Menova Health is a doctor-led Australian telehealth clinic. The process starts with a health assessment, after which a registered doctor reviews your symptoms and history, arranges blood tests where indicated and discusses options suited to your situation. Not everyone is eligible for every treatment; suitability is determined by the doctor following consultation.

You can read more about our medical weight management programme and hormone restoration services, including what an initial consultation involves. Responses to any treatment vary between individuals.

Frequently asked questions

Why is it harder for men to lose weight after 40?

Muscle mass declines gradually from your 30s, which lowers the energy your body uses at rest. Movement and sleep also tend to drop in busy years. The same eating habits then produce slow weight gain. Rebuilding muscle through strength training and adjusting food intake addresses both sides.

Can low testosterone make it harder to lose weight?

It can contribute. Testosterone supports muscle mass, and less muscle means a slower metabolism. The link also runs the other way, because carrying excess weight is associated with lower testosterone. A blood test arranged by a doctor is the only reliable way to know whether your level is low.

Does losing weight increase testosterone?

Often, yes. Healthy Male reports that weight loss can significantly increase testosterone levels, especially in men with more weight to lose. Better sleep, regular exercise and a healthier diet support the same shift. Doctors usually address weight and lifestyle before or alongside any discussion of hormone treatment.

How much exercise do I need to lose weight after 40?

Australian guidelines recommend 150 to 300 minutes of moderate activity each week, or 75 to 150 minutes of vigorous activity, plus strength training on at least 2 days. For men over 40 the strength sessions matter most, because they protect the muscle that keeps your metabolism working.

How do I know if my hormones are the problem?

Symptoms such as low energy, reduced sex drive, poor sleep and increased body fat can suggest low testosterone, but they overlap with many other causes. A doctor can arrange a morning blood test, with a second test to confirm any low reading, before considering a diagnosis.

Is testosterone therapy a weight loss treatment?

No. Testosterone therapy treats diagnosed testosterone deficiency and is prescribed only where a doctor finds it clinically appropriate. Healthdirect notes its benefit is unclear in older men without a testicular or pituitary problem. Weight management relies on diet, activity, sleep and doctor-supervised support where suitable.

References

• Healthdirect (2024). Obesity. https://www.healthdirect.gov.au/obesity
• Healthdirect (2024). Low testosterone. https://www.healthdirect.gov.au/low-testosterone
• Healthdirect (2024). Weight loss and dieting. https://www.healthdirect.gov.au/weight-loss-and-dieting
• Healthdirect (2025). Strength training for beginners. https://www.healthdirect.gov.au/strength-training-for-beginners
• Healthy Male (n.d.). Factors that affect your testosterone levels. https://healthymale.org.au/health-article/factors-affect-your-testosterone-levels
• Better Health Channel (2023). Physical activity, it's important. https://www.betterhealth.vic.gov.au/health/healthyliving/physical-activity-its-important