Are your male hormones the reason you can't lose fat?

Are you finding it difficult to shift winter body fat? It may be that your hormones are hindering your progress.

When it comes to fat loss, your calorie balance is always going to be key, regardless of macronutrients, genetics, metabolism, or anything else. But some things make losing fat more difficult.

We’re talking about hormones like testosterone, thyroid-stimulating hormone (TSH), and cortisol. Even minor imbalances can affect your body’s metabolism and the way it stores fat. But before we discuss why, it’s worth revisiting the fundamentals of caloric balance. 

The caloric balance equation

The rules are simple. If you are in a calorie deficit (eating less than you burn), you will lose body fat. If you are in a calorie surplus (eating more than you burn), you will gain fat.

Consider the extreme: if you stop eating entirely, you’ll lose body fat regardless of what your hormones are doing. Likewise, even if you have a slower-than-average metabolism and you’re someone who puts on weight easily, you’ll still lose body fat in a genuine calorie deficit.

But there is a threshold where the balance tips in the other direction. This maintenance value — quoted as 2,500 calories on average for men — is not fixed and is unique to each person. It’s influenced by your physical activity, height, weight, age, and metabolism. For example, a short and slim office worker may only need 2,000 calories to maintain their body weight, whereas a tall, muscular bodybuilder may need something closer to 5,000 calories. It’s important to be aware of this as your maintenance calories may be very different to what you expect.

If you’re eating 2,500 calories of crisps and ice cream, this will have a different effect than 2,500 calories of mixed vegetables. The latter contains more fibre, so less will be directly absorbed, as well as many more essential micronutrients that contribute to your health. 

So where do hormones come in?

Hormones play a role in body composition and metabolism. This means that an imbalance can effectively reduce your maintenance value and therefore make it harder to lose fat. Hormones may also alter your eating habits by affecting your appetite and mood. But which hormones are key? 

Four hormones that affect appetite and mood for men

1. Testosterone

Testosterone is one of the male sex hormones and it can have a significant impact on fat loss. Low testosterone can alter body composition to decrease lean muscle mass and increase body fat [1]. It can also affect mood and energy levels which may encourage unhealthier eating habits.

If you’re struggling to lose body fat, it may be worth checking your testosterone levels with our Testosterone Blood Test. This is especially true if you’ve struggled to lose weight despite following a diet and fitness regime consistently, along with symptoms like having a low sex drive. 

Borderline low levels of testosterone are generally best treated with lifestyle changes. Find out how you can boost your testosterone levels naturally. 

In rare cases, low testosterone is significant enough to warrant treatment with testosterone replacement therapy (TRT). If this is you, TRT is likely to make it easier for you to lose body fat provided you live a healthy lifestyle alongside your treatment.

Summary: Low testosterone may make fat loss more difficult, but it won’t stall it entirely. Adopting healthy lifestyle habits can not only help you lose weight but help you to boost your testosterone levels too.

2. Cortisol 

When you’re stressed, your body releases stress hormones like adrenaline and cortisol as part of the body’s fight or flight response. This is fine, at least in the short term, but it becomes a problem you’re stressed all the time. 

Chronic stress is linked to [2]:

  • High blood pressure
  • Insomnia
  • Headaches and migraines
  • Chronic inflammation
  • Impaired immunity
  • Cardiovascular disease
  • Depression and anxiety

Cortisol stimulates your appetite for higher-calorie foods which can lead to poorer diet choices and subsequent weight gain [3]. Cortisol also inhibits the effects of other hormones, which can lead to an increase in visceral fat (the ‘hidden fat’ stored around the organs) [4]. High levels of visceral fat increase your risk of type 2 diabetes and coronary heart disease. 

It’s therefore important to reduce stress where you can. There are many ways you can combat stress, such as exercising regularly and introducing stress-busting activities into your daily routine like yoga or meditation. See our top ten ways to de-stress

You can measure your cortisol levels with our Stress Cortisol Saliva Blood Tests (4)

Summary: Reduce the negative effects of cortisol through good sleep hygiene, regular exercise, and mindful activities, which will have beneficial effects on fat loss. 

3. Thyroid hormones

Thyroid hormones affect metabolism, so they can have a direct impact on your weight. Weight gain is common when the thyroid is not producing enough thyroxine (an underactive thyroid). This condition most commonly affects women over 50 but it can affect anyone at any age.

The good news is that treatment is often very effective with medications or surgery. If you’ve gained weight due to a thyroid problem, you’re likely to see improvements with treatment, as long as you lead a healthy lifestyle alongside. 

If you’re worried you may have a thyroid condition, you can check your thyroid-stimulating hormone levels with our Thyroid Function Blood Test.

Summary: Thyroid problems rarely affect men, but when they do, they may cause weight gain (or weight loss).Visit your GP if you’re concerned.

4. Insulin

Insulin has several roles in the body. It helps to control blood sugar levels by stimulating tissues to absorb sugar from the bloodstream. Insulin also promotes fat storage, but this only really becomes a problem if you’re eating too much (i.e., a calorie surplus) or if you’re diabetic.

Being overweight or physically inactive increases your risk of insulin resistance and developing prediabetes or type 2 diabetes. As insulin becomes less effective, the pancreas tries to create more insulin to compensate, but it can eventually tire. One of the best ways to combat pre-diabetes or type 2 diabetes is to lose weight. This can be tricky, particularly as one of the side effects of diabetes medications, including insulin, is weight gain.

Check your blood sugar control with our Diabetes (HbA1c) Blood Test. This gives you an idea of your blood sugar levels over the last three months and can determine whether you may have prediabetes or diabetes.

Summary: While insulin itself may promote fat storage, this is only relevant if you’re eating too much. Reducing insulin resistance is important in diabetes. One of the best ways to achieve this is with weight loss. 

Can hormones prevent fat loss?

A hormone imbalance can’t prevent fat loss on its own — your calorie balance has the final say. Diet and exercise will always be the most important contributing factors. But there are a few hormone conditions that may make fat loss more difficult. The good news is that most of these are treatable.

Keep up the good work and if you’re worried something else might be going on, consider a blood test to check your hormone levels, or visit your GP.

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  1. Ng Tang Fui, M., Prendergast, L., Dupuis, P., Raval, M., Strauss, B., Zajac, J. and Grossmann, M., 2016. Effects of testosterone treatment on body fat and lean mass in obese men on a hypocaloric diet: a randomised controlled trial. BMC Medicine, 14(1).
  2. Schneiderman, N., Ironson, G. and Siegel, S., 2005. Stress and Health: Psychological, Behavioral, and Biological Determinants. Annual Review of Clinical Psychology, 1(1), pp.607-628.
  3. Torres, S. and Nowson, C., 2007. Relationship between stress, eating behavior, and obesity. Nutrition, 23(11-12), pp.887-894.
  4. Van der Valk, E., Savas, M. and van Rossum, E., 2018. Stress and Obesity: Are There More Susceptible Individuals?. Current Obesity Reports, 7(2), pp.193-203.

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