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Medichecks sports doctor Emil Hodzovic explains more about how hormones can affect weight loss.
If you're struggling to lose weight, could a hormone imbalance be to blame? In short, yes and no.…helpful right?!
Basically, when it comes to fat loss, your calorie balance is always going to be the master key regardless of macronutrients, hormones, genetics, metabolism or anything else. If you are in a calorie deficit (eating less than you burn) then you will lose body fat. If you are in a calorie surplus (eating more than you burn) then you will gain fat [1,2,3,4]. I’m not saying that hormones, genetics or macronutrients don’t play an essential role in all of this, they are HUGELY important. But they will never override the energy balance equation.
This may be different from what you’ve heard, especially regarding hormones and weight loss.
Let me explain. Consider the extreme – if you stopped eating entirely you would lose body fat regardless of what your thyroid, insulin or cortisol was doing . As the calories go up, the deficit reduces until you hit your calorie maintenance value (quoted at 2500 calorie for guys) where your body weight becomes steady. It rapidly gets more complicated in real life as this maintenance value will vary from day to day and hormones and genetics (as well as height, weight, age and physical activity level etc) will significantly alter where this value stands, but there will always be a point where you are in a deficit.
This means that your maintenance calories can and should be optimised as this will ensure sustainable, realistic, long-term fat loss. You can do this by improving hormone health, eating and enjoying good quality food and exercising regularly – this will make your life easier AND improve your health! On top of this, hormones can affect appetite, hunger, water balance, mood and muscle mass so although hormone imbalance is not a complete show-stopper it can make fat loss a nightmare.
1. Hormones can never stop fat loss on their own. Your food intake is the final say.
2. Hormones can be optimised to make fat loss easier (and I’ll explain how and when you need to get checked out below).
3. Often losing fat and doing exercise will optimise hormones which in turn make fat loss and exercise easier etc. etc. so it becomes an upward spiral.
4. Eating good healthy food and exercising is vital for health and long-term sustainable fat loss.
The main culprits for this diet rollercoaster in men are testosterone, cortisol and the thyroid hormones but there are other hormones that are relevant as well. These include the hunger and appetite hormones ghrelin and leptin and of course no discussion about fat loss can occur without talking about insulin.
Insulin is responsible for storing fat BUT, this is only significant if you are eating too much (i.e. calorie balance). If you are overweight and insulin resistant (e.g. type 2 diabetes and prediabetes) then the best way to improve the situation is to lose weight by reducing calorie intake [6,7,8].
Ghrelin and leptin moderate hunger and appetite . There isn’t much to say – these can reset your hunger point if you are overweight, making dieting more difficult but there is nothing much that can be done about this apart from stacking the odds in your favour and powering through. Settle in and commit to the long game and it will improve with time.
Testosterone is the main male hormones and can have a pretty significant impact on fat loss. Low testosterone can cause decreases in muscle mass, mood and energy and increases and body fat. On top of this, high levels of body fat can decrease testosterone which makes this a negative loop which can be tricky to get out of .
My recommendation is two-fold. First off, take steps to improve your lifestyle and naturally boost your testosterone levels. I’ve written a whole article on this very topic which can be found here. Secondly, it may be worth getting your testosterone levels checked, especially if you are concerned or struggling to lose weight despite consistent diet and exercise. If your levels are borderline and don’t warrant treatment, then it may just be a case of continuing to improve your lifestyle. They should increase. Occasionally they require medical assistance and it would be wise to see your GP if that is the case.
THE BOTTOM LINE: Low testosterone may make fat loss more difficult, but it won’t stall it entirely and fat loss and a healthy lifestyle should cause it to improve.
Cortisol is the stress hormone and small amounts are absolutely essential for survival. It moderates metabolism controls inflammation and can have a positive effect on mood. However, chronic (long term) stress can be a real issue and high levels of stress can cause us to make poor food choices and crave more calorific food . This can make us pile on the pounds from eating excess calories and if your mood is low from stress then this is going to negatively impact dieting as well .
On top of this, cortisol can cause water retention, and this alone can be enough to derail a diet by playing with the number on the scales and the motivation of the individual. The good news is that lifestyle changes which help with stress also help fat loss. These include exercise, sleep and good food. Meditation can also help combat stress by rewiring how you think, helping to reframe stressful situations.
As with testosterone, medical intervention may be required (but this is rare). Cushing’s syndrome is an excess of cortisol, most often due to medication prescribed by your doctor (specific drugs such as prednisolone or hydrocortisone). There can very occasionally be other causes. If you are concerned about this then it is worth seeking further medical advice or testing.
THE BOTTOM LINE: Control your stress through sleep, meditation, exercise and social interaction to reduce the negative effects of cortisol and these will help with the fat loss as well.
Thyroid hormones directly control metabolism so are often related to or blamed for weight gain. The good news is that thyroid issues are treated routinely with hormone replacement and even untreated hypothyroidism won’t totally halt fat loss. Additionally, the weight gain associated with untreated hypothyroidism is not hugely significant (around 5-10lbs) which means that simply seeking treatment won’t cause everything to suddenly fix itself. A healthy lifestyle is still required [13,14]. That said, hypothyroidism is reasonably common (mainly in females but males too ) and can often go undiagnosed and untreated for some time  and there is no doubt that treatment will help.
THE BOTTOM LINE: Get it treated if it’s an issue. Implement lifestyle changes regardless as treatment won’t help alone.
So, as you can see there are a few conditions related to hormone health that can make fat loss more difficult, but the good news is diagnosis and treatment is available. A healthy lifestyle will also universally be required, however. For those where the hormone levels are borderline or don’t quite warrant treatment then the good news is that a healthy lifestyle can literally turn your life around.