Why Can't I Lose Weight? What Gets in the Way and What Helps

You're eating better than you have in years. You take the stairs, you walk at lunch, you said no to the cake in the staff room. And the weight round your tummy hasn't moved. Your jeans still dig in when you sit down, you're hungry an hour after lunch, and by 3pm the biscuit tin knows you by name.

If you've typed "why can't I lose weight" into your phone late at night, you're far from the only one. Many people tell me they've done every diet going, lost a stone, and watched it come back with a friend. It's rarely about willpower. Hunger, sleep, stress, hormones, muscle and the medicines you take all have a say, and when one of them is working against you, eating less on its own often isn't enough.

I'm now a prescriber, so I can go through all of it with you, work out what's getting in the way, and, if it's right for you, prescribe treatment alongside the changes to your food and training. You can see me online by video call from anywhere in the UK, or in the clinic in Milton Keynes.

Why can't I lose weight when I'm eating well?

Because eating well and eating less aren't the same thing, and because hunger, sleep, stress and muscle can all make weight harder to lose even when your food is good.

Healthy food still counts. Granola, nuts, olive oil, smoothies, oat lattes and a glass of wine with dinner are easy to like and easy to underestimate. Many people find that when they write down a normal day, the total surprises them.

Short sleep makes you hungrier. Research shows that after a short night, people tend to feel hungrier and reach for sweeter, starchier food the next day. If you're up at 3am or on early starts, your appetite is working against you before breakfast.

Stress keeps the hunger on. Long-term stress keeps cortisol (your main stress hormone) higher for longer, which can increase appetite and make it easier to store fat around your middle. There's more on this in cortisol, stress and weight around your middle.

Less muscle means your body needs less food. Muscle uses energy even when you're sitting still. Years of dieting without strength training can strip muscle away, so the same plate of food that kept you steady at 30 can add weight at 45.

Some medicines make weight gain more likely, such as steroids and some medicines for mood, sleep, epilepsy or diabetes. Don't stop anything on your own. Bring the list to your appointment and we go through it together.

Can hormones stop you losing weight?

They can make it a lot harder. Perimenopause and menopause, low testosterone in men, an underactive thyroid and insulin resistance can all make weight easier to gain and slower to lose.

Perimenopause and menopause. As oestrogen falls, many women find weight settles round the middle, sleep gets worse and cravings get stronger. HRT isn't a weight loss treatment, but for some women body-identical HRT helps sleep, mood and energy, which makes everything else easier to keep up. HRT also works well alongside a weight-loss medicine: in one study of real patients, women on HRT lost more weight on semaglutide than women who weren't, and my view is that your hormones should be kept balanced while you lose weight. How we combine them · the Menopause (HRT) Consultation.

Low testosterone, in women and men. In men, low testosterone and extra weight round the middle often go together, each can make the other worse, and low levels can take away strength, energy and sex drive. In women, low desire is the best-known sign, and many women tell me their energy and strength come back too. Weight loss raises men's own testosterone, and testosterone helps keep muscle while the weight comes off, so the two can be planned together. Read more about testosterone.

An underactive thyroid slows everything down: you're tired, cold, constipated, your skin is dry, and some weight goes on. A blood test checks it.

Insulin resistance means your body needs more and more insulin to deal with the same food. High insulin makes it easier to store fat around your tummy and harder to use it. Many people notice an energy crash after meals, sugar cravings, skin tags, or darker, velvety skin on the neck or in the armpits. In women, PMOS (polyendocrine metabolic ovarian syndrome, the new name for PCOS) often comes with it.

Which blood tests help when you can't lose weight?

Usually blood sugar, a full thyroid check, iron, B12 and vitamin D, cholesterol and liver, and your hormones if your symptoms point that way.

Blood sugar is checked with HbA1c (your average blood sugar over the last 2 to 3 months). We check more than one thyroid marker, because TSH (thyroid-stimulating hormone, the usual first test) on its own can miss part of what's going on. Low iron, B12 or vitamin D can leave you too tired to train, and liver and cholesterol results help us plan safely.

Treatment can often start before any blood test, and the results help us adjust the plan at your review. If you've had bloods done recently, bring the numbers, not just "normal". A result can sit inside the range and still tell us something.

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Blood tests you can order and do from home

Is weight loss treatment right for me?

It might be. It depends on your height and weight, your health, your history and what you want, and we decide that together.

Being a prescriber doesn't mean everyone leaves with a prescription. Where treatment is right for you, it sits alongside food, strength training and sleep, because those help you hold on to more of what you've lost once treatment stops. If it isn't right for you, or you'd rather not take anything, the rest of the plan still works on your weight.

There are height and weight limits for medical weight loss treatment, and some health conditions change them, so we check yours at the appointment. Weight loss treatment isn't used if you're pregnant, breastfeeding or trying to get pregnant. Before anything starts, we go through what to expect, the side effects and how to manage them, and we start slowly.

Nobody can promise you a number, and results vary a lot from person to person. If you're already on treatment from somewhere else, bring the name, the dose and when you started, and we decide together whether to carry on or change the plan.

If we agree on a treatment, it's posted to your home through our pharmacy partners. If your prescription is approved before 4pm, it's usually with you the next working day.

Will I lose muscle when I lose weight?

Some of any weight you lose is muscle, which is why protecting it is part of every weight plan we make.

Muscle keeps you strong on the stairs, helps your body handle blood sugar, and uses energy even when you're resting. Lose it along with the fat and you can end up lighter but weaker and more tired, which nobody signs up for.

Protecting it comes down to 2 things. Protein at every meal, eaten first so you get it in before you're full, to keep muscle while you eat less. And strength training at least 2 days a week, whether that's weights, resistance bands or bodyweight exercises at home. Your plan gives you meal ideas you'll actually want to cook, and a starting point that fits your week, even if you haven't lifted anything heavier than a shopping bag in years.

What happens in a Weight Loss Consultation?

It's 25 minutes, online by video call from anywhere in the UK, or in the clinic in Milton Keynes. We go through your weight history and your health, and agree a plan together.

We talk about what you eat, how you sleep, your stress, your gut, your hormones, the medicines you take and what you've already tried. Then we work out what's most likely getting in the way. If treatment is right for you, we decide together and it can start straight away, with blood tests arranged where they'd help. At your review we look at how you're getting on, your side effects and your energy, and adjust the plan. Talk, start, test, review, with the same person each time.

Before your appointment, write down roughly what your weight has done over the years, the diets you've tried, the medicines and supplements you take, and any recent blood results.

The Weight Loss Consultation is for anyone over 18. Book your Weight Loss Consultation, or see every appointment on the Book online page.

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Debora Tentis, Women's Health Pharmacist Prescriber.