Wegovy Weight Loss Results: What the Data Shows

Wegovy (semaglutide 2.4 mg) produces average weight loss of 15% of body weight over 68 weeks, according to clinical trial data. In the landmark STEP 1 trial, 86% of participants lost at least 5% of their body weight, 69% lost at least 10%, and about half achieved weight loss of 15% or more. Beyond weight loss, the SELECT trial demonstrated a 20% reduction in major cardiovascular events like heart attacks and strokes, making Wegovy the first weight loss medication proven to reduce cardiovascular risk.

These results represent some of the most significant outcomes ever seen with a weight loss medication. But averages only tell part of the story. Let’s examine what the research actually shows and what you can realistically expect.

The STEP Trials: The Foundation of Wegovy’s Approval

Wegovy’s FDA approval was based primarily on the STEP (Semaglutide Treatment Effect in People with Obesity) clinical trial program. These large scale studies tested semaglutide 2.4 mg in thousands of participants across different populations and conditions.

The STEP 1 trial, published in the New England Journal of Medicine, enrolled nearly 2,000 adults with obesity or overweight (with at least one weight related condition) who did not have diabetes. Participants received either semaglutide 2.4 mg weekly or placebo, along with lifestyle counseling.

After 68 weeks, the results were striking:

The treatment difference of 12.4 percentage points represents the medication’s effect beyond what lifestyle changes alone produce. This gap is larger than any previously approved weight loss medication.

Long Term Results: The STEP 5 Trial

One question about any weight loss intervention is whether results last. The STEP 5 trial followed participants for two full years to answer this question.

At 104 weeks, participants taking semaglutide had lost an average of 15.2% of their body weight, compared to 2.6% with placebo. Importantly, weight loss achieved by week 52 was maintained through week 104, suggesting that continued treatment prevents regain.

The breakdown of results at two years:

• 77% lost at least 5% of body weight
• 62% lost at least 10%
• 52% lost at least 15%
• 36% lost at least 20%

These numbers demonstrate that Wegovy can produce sustained weight loss when treatment continues, though they also highlight that maintaining results requires ongoing medication.

Real World Results: Beyond Clinical Trials

Clinical trials involve carefully selected participants and intensive support. What happens in everyday practice?

A real world study examining over 4,400 patients taking Wegovy for a full year found encouraging results. After 52 weeks, average weight loss was 15.5 kg (about 34 pounds). The milestone achievements were:

• 88% lost at least 5% of body weight
• 72% lost at least 10%
• Nearly 50% lost at least 15%
• More than 25% lost at least 20%

These real world numbers actually slightly exceed clinical trial results, possibly because patients who continue treatment for a full year represent those who respond well and tolerate the medication.

Another study published in JAMA Network Open found that at 6 months, real world patients achieved 10.9% average weight loss, with 87% reaching the 5% threshold and 55% reaching 10%.

What Different Levels of Weight Loss Mean in Practice

Percentages translate differently depending on starting weight. Here’s what various weight loss levels look like in absolute terms:

At 200 pounds starting weight:

• 10% loss = 20 pounds (new weight: 180 lbs)
• 15% loss = 30 pounds (new weight: 170 lbs)
• 20% loss = 40 pounds (new weight: 160 lbs)

At 250 pounds starting weight:

• 10% loss = 25 pounds (new weight: 225 lbs)
• 15% loss = 37.5 pounds (new weight: 212.5 lbs)
• 20% loss = 50 pounds (new weight: 200 lbs)

At 300 pounds starting weight:

• 10% loss = 30 pounds (new weight: 270 lbs)
• 15% loss = 45 pounds (new weight: 255 lbs)
• 20% loss = 60 pounds (new weight: 240 lbs)

A 15% weight loss produces noticeable visual changes for most people. Clothes fit differently, facial features appear more defined, and others typically comment on the transformation.

Health Benefits Beyond the Scale

Weight loss numbers don’t capture the full picture of Wegovy’s benefits. Clinical trials documented improvements across multiple health markers.

Cardiovascular protection. The SELECT trial, which followed over 17,600 participants for nearly 4 years, found that Wegovy reduced the risk of major cardiovascular events (heart attack, stroke, or cardiovascular death) by 20% in people with obesity and existing heart disease. This makes Wegovy the first weight loss medication proven to reduce cardiovascular risk.

Blood pressure improvements. STEP trials showed average reductions in systolic blood pressure of about 6 mmHg with semaglutide compared to placebo.

Cholesterol improvements. Participants experienced reductions in triglycerides and improvements in other lipid markers.

Blood sugar benefits. Even in participants without diabetes, improvements in fasting glucose and HbA1c were observed. Among those with prediabetes, many normalized their blood sugar levels.

Waist circumference. Average reduction of about 5 to 6 inches in waist circumference was seen in clinical trials, reflecting loss of visceral (belly) fat.

Quality of life. Participants reported improvements in physical functioning and overall quality of life measures.

Who Responds Best to Wegovy?

Not everyone achieves the same results. Research has identified several factors that influence outcomes:

Diabetes status matters. People without type 2 diabetes tend to lose more weight than those with diabetes. The STEP 2 trial, which focused on participants with diabetes, showed average weight loss of 9.6% compared to 14.9% in STEP 1 (without diabetes). Both are meaningful, but the difference is notable.

Early response predicts long term success. Participants who lose at least 5% of their body weight by week 12 to 16 tend to achieve the best long term outcomes. Those who show little early response may be “non-responders.”

Dose achieved. Getting to and tolerating the full 2.4 mg dose produces better results than staying at lower doses. About 85% of trial participants reached the maximum dose.

Treatment duration. Weight loss continues for approximately 60 weeks before plateauing. Stopping earlier means missing potential additional weight loss.

Lifestyle factors. While Wegovy reduces appetite significantly, combining medication with improved nutrition and activity enhances results.

The Timeline of Weight Loss on Wegovy

Understanding when to expect results helps set realistic expectations:

Month 1 (dose: 0.25 mg): The starting dose is designed for tolerability, not weight loss. Expect minimal change, typically 1 to 2% of body weight. Side effects like nausea are most common during this period.

Months 2 to 3 (doses: 0.5 mg to 1.0 mg): Weight loss begins accelerating. By week 12, average loss is around 5% to 6% of body weight. Appetite suppression becomes more noticeable.

Months 4 to 6 (doses: 1.7 mg to 2.4 mg): You reach the full dose during this period. Weight loss continues steadily, averaging 10% to 12% by month 6. This is often when visual changes become obvious.

Months 7 to 12: Weight loss continues but at a gradually slowing pace. Most people reach 14% to 15% average loss by month 12.

Beyond 12 months: Weight typically stabilizes at its lowest point around week 60 to 65. Continued treatment maintains results; stopping leads to regain.

Comparing Wegovy to Other Options

How does Wegovy stack up against alternatives?

Versus other medications: Wegovy produces significantly more weight loss than older medications like phentermine, orlistat, or naltrexone/bupropion (Contrave). In head to head comparisons, semaglutide 2.4 mg outperformed liraglutide (Saxenda) by a substantial margin (15.8% vs 6.4% weight loss).

Versus tirzepatide (Zepbound): The SURMOUNT-5 trial directly compared tirzepatide to semaglutide. Tirzepatide produced 20.2% average weight loss compared to 13.7% with semaglutide, a 47% greater relative reduction. Both are highly effective, but tirzepatide appears to have an edge.

Versus bariatric surgery: The 20% weight loss achieved by roughly one third of Wegovy users approaches results seen with some bariatric procedures like gastric sleeve (typically 20% to 30% weight loss). However, surgery tends to produce more dramatic results in those with higher starting weights.

Understanding Non-Responders

About 13% to 15% of people taking Wegovy don’t achieve the 5% weight loss threshold considered clinically meaningful. Several factors may contribute:

Biological variation. Just as people respond differently to blood pressure medications, GLP-1 response varies between individuals for reasons not fully understood.

Dose limitations. Some people can’t tolerate higher doses due to side effects, limiting effectiveness.

Metabolic factors. Certain metabolic conditions may reduce response. People with type 2 diabetes, for instance, typically lose less weight than those without.

Behavioral factors. While Wegovy significantly reduces appetite, eating patterns and food choices still influence outcomes.

If you’re not seeing expected results after adequate time on the full dose, discussing alternatives with your provider makes sense. Semaglutide at different doses or tirzepatide might work better for some individuals.

Side Effects and Tolerability

Wegovy’s benefits come with potential side effects, primarily gastrointestinal:

Nausea affects roughly 44% of users, compared to 16% on placebo. It’s usually worst during dose increases and improves over time.

Vomiting occurs in about 25% of users.

Diarrhea affects roughly 30% of users.

Constipation is also common, sometimes accompanied by sulfur burps.

These side effects led about 7% of clinical trial participants to discontinue treatment. The gradual dose escalation schedule helps minimize severity. Most people find symptoms manageable and improving over time.

What Happens When You Stop Wegovy?

The STEP 4 trial examined what happens after discontinuing treatment. Participants who switched from semaglutide to placebo after 20 weeks regained about two thirds of the weight they had lost within the following year. Those who continued treatment maintained their weight loss.

This finding reinforces that obesity is a chronic condition requiring ongoing management. Wegovy works effectively while you’re taking it, but its effects don’t persist after stopping.

Getting Started With Semaglutide Treatment

If Wegovy’s results interest you, the first step is determining whether you’re a candidate. GLP-1 medications are typically appropriate for adults with a BMI of 30 or higher, or 27 or higher with weight related conditions like high blood pressure, prediabetes, or high cholesterol.

TrimRx offers telehealth consultations and access to compounded semaglutide, which provides the same active ingredient as Wegovy at a more affordable price point. You can take the intake quiz to see if you qualify.

The Bottom Line

Wegovy produces average weight loss of 15% over 68 weeks, with about half of users losing 15% or more and one third achieving 20% or greater weight loss. Beyond the scale, it’s the first weight loss medication proven to reduce cardiovascular risk, with a 20% reduction in heart attacks, strokes, and cardiovascular deaths.

Real world results closely mirror clinical trial findings, and two year data shows that weight loss can be maintained with continued treatment. The medication works best for those who can tolerate the full dose, respond early, and commit to ongoing treatment.

Individual results vary, and about 15% of users don’t achieve meaningful weight loss. But for the majority, Wegovy represents the most effective pharmacological weight loss option currently available outside of tirzepatide.

This information is for educational purposes and is not medical advice. Consult with a healthcare provider before starting any medication. Individual results may vary.