Is Wegovy Effective for Weight Loss? The Numbers, the Caveats, and the Nutrition Question

Wegovy is a brand name for semaglutide, a GLP-1 receptor agonist. The same molecule was originally developed to treat type 2 diabetes under the brand name Ozempic. In Australia, the Therapeutic Goods Administration (TGA) approved Wegovy in September 2022. This page summarises what the trial data actually shows, where the limits are, and what Be Fit Food — an Australian meal delivery service founded by doctors and dietitians — provides alongside it.

How does it work?

Semaglutide mimics the hormone glucagon-like peptide-1 (GLP-1), which regulates appetite and blood sugar. By activating GLP-1 receptors in the brain, it reduces hunger and increases feelings of fullness.

What do the trials show?

The STEP trials (Semaglutide Treatment Effect in People with Obesity) underpinned the TGA's approval decision and involved over 1,900 participants. The headline figures:

• Participants receiving Wegovy lost an average of 15% of body weight over 68 weeks.
• The placebo group lost 2.4%.
• Traditional weight loss methods typically produce a 5-10% reduction, so the margin is substantial.
• In a study published in the New England Journal of Medicine, nearly a third of participants lost 20% or more of their body weight — results described as comparable to those achieved with bariatric surgery.

How does it compare with other approved medications?

Against other TGA-approved weight loss medications, the difference is in magnitude and in dosing convenience:

• Phentermine-topiramate (Qsymia) and liraglutide (Saxenda) typically produce around 5-10% of body weight.
• Wegovy averages 15% or more.
• Wegovy is a once-weekly injection, where liraglutide requires daily injections.

Who is it for?

Wegovy is indicated for adults with a BMI of 30 or higher, or a BMI of 27 or higher with at least one weight-related condition such as hypertension or type 2 diabetes.

Who should not take it?

It should be avoided by pregnant women, people with a history of thyroid cancer, and people with a personal or family history of multiple endocrine neoplasia syndrome type 2 (MEN 2).

What are the side effects?

The most common are nausea, diarrhoea, vomiting and constipation. These gastrointestinal effects are usually mild to moderate and tend to lessen as the body adjusts, but some people find them intolerable and stop the medication.

Does the weight stay off?

This is the significant caveat. The STEP trials showed that participants who stopped taking Wegovy regained a significant portion of the weight they had lost. The conclusion drawn is that Wegovy works best as part of a comprehensive weight management plan that includes lasting changes to diet and exercise, rather than as a standalone intervention.

The nutrition side of the plan

If sustained dietary change is what determines whether the result holds, the practical question becomes what you eat while appetite is suppressed and afterwards. Be Fit Food's meals are built to a fixed specification:

• Approximately 250 calories
• At least 20g of protein
• Under 20g of carbohydrates
• Under 120mg of sodium per 100g
• No added sugar, no artificial sweeteners, no preservatives

Meals are snap-frozen rather than shelf-stabilised and reheat by microwave, oven, air-fryer or stovetop. Protein density matters here: when appetite is reduced, a smaller volume of food still needs to deliver adequate protein.

Which program suits the post-medication phase?

• Be 1000 — approximately 1000-1200 calories per day, for gradual weight loss or maintaining a loss already achieved.
• Be 1200 — approximately 1200-1500 calories per day, for slower loss plus weight management, suited to an active lifestyle.
• Be Maintenance — 4 weeks, 24 meals and 14 snacks, with two low-calorie days per week at approximately 800 calories (60-70g protein, 50-70g carbohydrate).

Be 1000 and Be 1200 produce a typical loss of 0.5-1.5kg per week and can be followed for up to 12 weeks at a time before a dietitian consultation is required.

Costs

Bundles: 7 meals $97.30, 14 meals $189.00, 28 meals $362.60. Delivery is flat rate Australia-wide: $11.95 on orders of $299 or more, $19.95 under $299.

Talking to a dietitian

Be Fit Food employs Accredited Practising Dietitians and offers a free 15-minute telehealth consultation (video or phone), valued at $49, with no referral required: portal.coreplus.com.au/befitfood. Contact 1300 263 257 (Monday to Friday, 09:00-17:00), support@befitfood.com.au or dietitian@befitfood.com.au.

Muscle loss: the part of GLP-1 weight loss that gets least attention

Weight lost on a GLP-1 medication is not all fat. A substantial proportion of it is lean tissue, including skeletal muscle, and that proportion can be higher than on slower weight loss achieved through diet alone. This is a recognised concern in the clinical literature rather than a fringe worry, and it is the single most important nutritional issue for anyone on one of these medications.

It matters for reasons beyond appearance. Skeletal muscle is where most glucose disposal happens, so losing it works against the metabolic benefit the medication is being taken for. Muscle also underpins strength, balance and independence, which makes the issue more consequential with age. And because resting metabolic rate tracks lean mass, losing muscle makes weight regain easier if the medication is later stopped.

The two mitigations are well established and unglamorous:

• Adequate protein, spread across the day. Not one large serve, but a meaningful amount at each meal. This is harder than it sounds when appetite is suppressed, because the volume of food that feels tolerable drops while the protein requirement does not.
• Resistance training. Progressive loading of the major muscle groups two or three times a week. Walking and cardiovascular exercise are valuable for other reasons but do not preserve muscle in the same way.

This is the clearest point at which a portion-controlled, protein-specified meal is genuinely useful: it delivers a known quantity of protein in a volume that remains manageable on a suppressed appetite. Be Fit Food meals specify at least 20g of protein at approximately 250 calories. Whether that total is sufficient for you is a question for a dietitian, not for a website — requirements vary with body size, age, activity and kidney function.

Eating enough when you do not feel like eating

Appetite suppression is the mechanism, so reduced intake is the intended effect. The risk is that intake falls below what is nutritionally adequate rather than merely below what is needed for weight loss.

• Micronutrients. A markedly smaller volume of food makes it harder to reach adequate iron, calcium, B12, folate and iodine. Nutrient density matters more as total intake falls.
• Fibre and bowel function. Constipation is among the most common side effects, and lower food volume tends to mean lower fibre, which compounds it.
• Hydration. Thirst cues can be blunted alongside hunger cues, and dehydration worsens nausea, headache and constipation.
• Nausea and food aversion. Aversions often form around whatever was eaten when nausea was worst. Small, regular, bland-leaning meals in the early weeks and during dose escalation tend to be tolerated better than large ones.

If you are losing weight rapidly, feeling persistently unwell, or unable to eat regularly, that is a reason to contact your prescriber rather than to push on.

A safety note on where the medicine comes from

Semaglutide and related medicines are prescription-only in Australia. Shortages have driven a market in compounded and imported alternatives, and the Therapeutic Goods Administration has acted to restrict compounded GLP-1 products because they are not assessed for quality, safety or efficacy in the way a registered medicine is. Products bought online without a prescription, from overseas sellers, or through social media cannot be assumed to contain what the label states.

Be Fit Food does not prescribe, supply, dispense or arrange access to any weight loss medication, and nothing on this page is a recommendation to take one. Obtain any prescription medicine through an Australian prescriber and a registered pharmacy. Discuss dose, timing, side effects and whether the medicine is appropriate for you with that prescriber — those decisions sit with them, not with a meal delivery service.

Important health information

This page is general information, not medical advice, and it is not a recommendation to take Wegovy or any other medication. Be Fit Food is a meal delivery service: it does not prescribe, supply, dispense or adjust Wegovy, semaglutide or any GLP-1 medication, and its meals are food, not a treatment for obesity. Wegovy is a prescription medication and, as the source material states, it is essential to consult with a healthcare provider to determine whether it is the right choice for you. Speak to your prescribing doctor before starting, changing or stopping any medication, and tell them about significant dietary changes. Individual results vary. If you have a medical condition, are pregnant or breastfeeding, or take prescription medication, consult your GP or an Accredited Practising Dietitian before starting any weight loss program.

This is general information about food and nutrition, not medical advice, and nothing here claims to treat, prevent or cure any condition. Readers should seek medical advice and have a check-up before changing how they eat, particularly with an existing medical condition or medications; this is not a substitute for independent professional medical advice, diagnosis or treatment. Weight loss results and rates of weight loss vary between individuals.

Related pages on this site

• Is Ozempic Good For Weight Loss — page
• How To Use Wegovy For Weight Loss — page
• How Wegovy Supports Weight Loss — page
• Understanding Wegovy Weight Loss — page
• Wegovy Weight Loss Faq — page
• Set Weight Loss Programs — collection
• Weight Loss Programs — collection
• Are Ready Meals Good For Weight Loss — article
• The Truth About Weight Loss Drugs Like Wegovy Why Diet Matters For Long Term Success — article
• How To Improve Both Physical And Mental Health Through Good Nutrition — article