The nifty injection trick to BOOST weight loss on fat jabs – and 6 ‘simple’ mistakes to avoid

FOR millions around the world, fat jabs like Mounjaro and Wegovy have been a godsend for a simple and stress-free way to shed those stubborn pounds.

But if you want to make the most of them, you need to be injecting the most effective way, and that’s not all… there are several mistakes you could be making that might be getting in the way of a slimmer you.

For some users, the GLP-1 weight loss jabs are not proving to be the fat-busting gift they were led to believe they would be.

Often it’s not down to the drugs failing, but rather mistakes people make – including how exactly they use the pens.

Kirsten Davies, a nutritionist from weight loss drug provider CheqUp, tells Sun Health: “GLP-1 medications can be powerful tools for weight loss, but they’re not magic.”

“Without the right approach to food, exercise and self-care, these drugs won’t work the way people expect them to.”

One Reddit user, who had taken Mounjaro for seven weeks, said: “I don’t feel like there’s any appetite suppression and there’s definitely no loss of food noise, all I want to do is eat still.”

Another added: “I’ve been on Mounjaro for about four months, now on 12.5mg and literally only lost like 5lbs.”

Meanwhile, another person who had been taking the same tirzepatide-based drug for a whole year said they had only lost 5lbs.

“My entire medical team can’t figure out why this drug isn’t working on me,” they explained.

One user even started a Reddit thread called ‘feeling broken on Mounjaro – it’s not working’, asking other people for help after gaining weight on the drug.

After six weeks on Monjaro, they said: “I see my body in the mirror and it looks bigger, I am always bloated.”

Clinical trials have revealed that more than 13 per cent of people taking semaglutide (Wegovy and Ozempic) and nine per cent of those on tirzepatide are “non-responders”.

That means they failed to lose at least five per cent of their body weight within the first three months.

These drugs are part of a class known as Glucagon-like peptide-1, or GLP-1 receptor agonists. They mimic a natural gut hormone that helps regulate blood sugar, curb appetite, and slow digestion so you stay fuller for longer.

Dr David Huang, director of clinical innovation at weight loss service Voy, tells Sun Health: “These meds help suppress appetite, but also seem to reconfigure the brain to avoid unhealthy habits and prioritise better foods.

Are you jabbing correctly?

If you’re not seeing results, it could be down to using the pen incorrectly, says Ana Carolina Goncalves, a pharmacist at Pharmica in Holborn, London.

But also, another common mistake is injecting the jab in the same spot each time.

Dr Crystal Wyllie, GP at Asda Online Doctor, explains: “People often default to injecting in the same spot over and over, but this can cause local irritation or even small lumps of fat under the skin (lipohypertrophy).

“This can affect how well the medication is absorbed and make it less effective.”

She recommends rotating injection sites between the abdomen, thigh, and upper arm, and even picking different spots within those zones.

Ana explains how to use the pens correctly: Attach a fresh needle and turn the dial to the priming setting (usually shown with a droplet symbol or small number).

Always jab in the stomach? It’s time to shake it up and see if your results boom[/caption]

Hold the pen upright with the needle pointing up, then tap it lightly to move any air bubbles to the top.

Press the dose button and check for a drop of liquid at the tip.
If nothing appears, repeat the process.

If it still doesn’t work, change the needle or speak to a pharmacist for help.

Ana says: “When injecting, hold down the dose button long enough to deliver the full dose.

“Releasing too early can cause medication to spill and reduce effectiveness.”

Here are the six other mistakes you could be making…

1. Time it right

Are you choosing the right day to take your jab?

One common mistake is expecting it to work instantly.

For example, taking it right before a takeaway, special occasion, or big night out in the hope it will stop you from overindulging.

Jason Murphy, head of pharmacy and weight loss expert at Chemist4U, says: “Taking the jab right before a takeaway or party won’t automatically stop you from indulging.

“Weight loss injections need time to build up in your system.

“They don’t blunt your appetite immediately after injection.

“It usually takes a few days to start feeling a difference, and several weeks for the full effects to settle in.”

Inject your dose mid-week if you plan for a heavier weekend.

2. Eat right

If the jabs are working, you shouldn’t feel the urge to overeat at mealtimes.

But skipping meals altogether can backfire, warns Dr Huang.

He explains: “If a person becomes extremely malnourished, their body goes into an emergency conservation state where their metabolism is slowed down to the extent that weight loss may plateau.

The goal is not starvation, which can have negative effects on brain, bone, muscles and long-term health

David Huangdirector of clinical innovation at weight loss service Voy

“It also makes the weight loss very unsustainable in the long term, and there can be a bounce-back effect when patients re-feed.”

In other words, starving yourself will slow down your metabolism, making it harder to lose weight but easier to regain once you stop using the jabs.

“The goal is not starvation, which can have negative effects on brain, bone, muscles and long-term health,” Dr Huang says.

Kirsten says up to 80 per cent of her weight-loss clients skip breakfast, thinking it will help speed up weight loss, but it instead leaves you running on empty.

“It may seem harmless, but going too long without food can cause your blood sugar to drop and that signals stress to the body,” she warns.

“In response, your system releases cortisol, your primary stress hormone, which then tells your liver to release stored sugar into your bloodstream.

“This can lead to a blood sugar spike even though you haven’t eaten, which can lead to more cravings and so more weight gain.”

Don’t starve yourself, as this could have health implications[/caption]

4. Food for thought

A key mistake with weight-loss jabs is not eating the right foods.

Since you’re eating less, it’s even more important to make sure your body is properly fuelled

“You can’t chase weight-loss treatments with burgers and expect miracles,” warns Mital Thakrar, a pharmacist from Well Pharmacy.

“Cut out sugary drinks and alcohol and focus on whole foods, lean proteins, fibre, and hydration.”

Protein, including lean meats, fish, eggs, beans, and tofu, protects muscles.

While fibre, found in fruit, vegetables, and nuts, keeps you fuller, stabilises blood sugar, and supports gut health.

Dr Vishal Aggarwal, Healthium Clinics, says: “Reduced protein intake can cause muscle loss rather than fat loss.

“Maintaining protein helps preserve muscle, supports metabolic health, and promotes sustainable weight loss.”

5. Thirsty work

Not losing weight? Dehydration could be to blame.

Staying topped up with water is one of the simplest ways to support the jabs

Dr Wyllie says: “Dehydration is a common, yet indirect, side effect of weight loss injections.”

Fat jabs dull both your appetite and thirst cues.

Drinking enough water, increasing fibre slowly, and gentle exercise can help constipation.

Dr Crystal WyllieGP at Asda Online Doctor

But staying hydrated is always important for your body to function properly.

He adds: “Aim for two to three litres per day, sipping regularly, not just when thirsty.

“Hydration supports metabolism, digestion, and can reduce side effects like headaches, nausea, and constipation.”

These may seem minor side effects, but they can slow your progress by leaving you fatigued or uncomfortable.

Dr Wyllie says: “Drinking enough water, increasing fibre slowly, and gentle exercise can help constipation.

“If needed, over-the-counter remedies are an option, but talk to a pharmacist if symptoms persist.”

6. Move it

It’s easy to see the jabs as a quick fix and let them do the heavy lifting.

“People might slow down or stop exercising altogether,” says Mr Thakrar.

“But exercise helps maintain muscle mass during weight loss, improves insulin sensitivity, and boosts mood and metabolism.”

Just 30 minutes of walking a day can help the meds work better by lowering blood pressure and improving overall well-being, he says.

Exercising to preserve muscle mass can help shape your body as you lose weight, which may be crucial if you are experiencing excess skin.

Exercise on the jabs to prevent muscle deterioration[/caption]

7. Quit it

One big mistake some people make with skinny jabs is stopping them too suddenly.

Mr Thakrar warns this can lead to rapid weight regain.

“There’s a tendency to ditch weight-loss treatments as soon as you reach your desired weight,” he says. “But that’s not our advice.”

A recent University of Oxford study found people typically return to their original weight within 10 months of stopping treatment, especially if lifestyle changes weren’t firmly established.

“Without the appetite suppression, hunger and cravings return quickly,” Mr Thakrar explains.

This includes healthier eating, which means cutting out junk food and alcohol while increasing protein and fibre, as well as exercising regularly.

“Building habits like these during treatment is key for sustaining results,” Mr Thakrar advises against stopping medication without medical advice.

“Many patients see improvements in blood sugar, cholesterol, and blood pressure,” he says.

But stopping too soon can reverse these gains if weight creeps back.