Ozempic, Wegovy or Metformin? For Weight Loss or for Type 2 Diabetes (T2D)?

Both Ozempic and Wegovy are prescription medications originally designed for T2D by improving glycemic control, lowering blood sugar, and increasing insulin production. Both contain the same active ingredient semaglutide, which is known to cause significant and rapid weight loss by mimicking a hormone that slows digestion and suppresses appetite and as a result may people are taking these drugs for weight loss.

Metformin more typically taken for T2D, rather than as a weight loss drug, does cause more modest weight loss, often reported as 1–3 kg (2–7 lb) over 6–12 months. Metformin reduces glucose production in the liver and improves insulin sensitivity reducing food cravings and over eating.

What are the side effects of semaglutide drugs?

Studies in 2025-2026 have found the following side effects:

•  Gastrointestinal (GI) issues: nausea, vomiting, and abdominal pain and increasing the dose too quickly causes rapid escalation of GI side effects
• Higher incidence of bone fractures and tendon injuries suggesting a significant increase in risks like osteomalacia. (a condition causing soft, weak bones due to defective bone mineralization caused by vitamin D deficiency.)
• Hair loss can be a side effect semaglutides, affecting up to 1 in 10 people taking these drugs due to significant weight loss and depletion of nutrients. The drug manufactures reassure patients that this hair loss is transient and reversible and that hair will regrow over the subsequent 3-6 months.
• Preliminary studies show that semaglutide carries a boxed warning regarding a potential risk of thyroid C-cell tumors.
• Pemaglutides are associated with an increased risk of vitamin D deficiency and users have a significantly higher risk compared to those on other diabetes medications. 
• Potential Vision Issues: A 2024–2025 study reported a potential, rare association with Nonarteritic Anterior Ischemic Optic Neuropathy (NAION), a condition that can cause sudden vision loss.
• Muscle weakness some research suggests the loss of lean mass might lead to muscle weakness, rather than just loss of muscle volume that comes with weight loss.
• Stopping semaglutides typically causes a rapid return of appetite and weight regain within a few years. 

  Weight regain occurs roughly four times faster after discontinuing semaglutides compared to stopping traditional weight loss diet and exercise programs, averaging a return of about 10 pounds (4.8 kg) in the first year after stopping. Research published in the British Medical Journal indicates that individuals often regain two-thirds or more of lost weight, with an average weight gain rate of 0.4 kg/month.

Metformin can cause a metallic taste in the mouth, loss of appetite and in about 25% of the users it can cause GI issues such as nausea, vomiting, diarrhea, bloating, gas, and stomach pain.
It can also cause long term vitamin B-12 deficiency. symptoms can range from fatigue, cognitive impairment, neuropathic pain (pins and needles), balance problems, irritability, depression, and more.

These drugs can be a temporary weight loss treatment, they are not a cure, nor do they come without risks. If you are taking these drugs for weight loss, you have the choice to stop but if you are taking them for T2D then you can continue or change to a different from of diabetic medication such as metformin which comes with fewer side effects.

If you are taking the semaglutides for a short term for initial weight loss while at the same time, changing  poor lifestyle habits  and shifting to a healthy program such as the Mediterranean Diet and regular exercise then there will be less chance of rapid weight regain upon stopping the medication because you have made changes  that support a healthy weight.

While taking semaglutides for weight loss or T2D consider taking supplement support to prevent nutrient deficiencies caused by these drugs.

Nutrient deficiencies caused by semaglutides include:
 Semaglutides cause nutrient deficiencies by slowing gastric emptying (slower digestion) and significantly reducing appetite, leading to lower food intake. Deficiencies are most likely to occur in the first 6 months of treatment due to rapidly reduced food intake.

 ·         Vitamin B12: Often considered the most significant deficiency risk, as slower digestion reduces its absorption. If taking metformin with semaglutide, the risk of B12 deficiency is increased.
·         Vitamin D deficiency is common particularly because many people already have lower levels due to obesity or T2D.
·         Thiamine (Vitamin B1) is a critical risk in the first 6 months, especially if there is severe restriction of food intake, nausea, or vomiting.
·         Iron deficiency anemia due to low food intake
·         Calcium & Magnesium deficiency due to reduced food intake combined with potential gastrointestinal side effects can lead to muscle weakness or bone loss.
·         Other Potential Deficiencies: Studies have also indicated lower levels of zinc, folate, and other fat-soluble vitamins (A, E, K) due to reduced overall caloric intake

A good multi-vitamin and mineral supplement can help prevent some of these deficiencies along with additional sublingual vitamin B12 and vitamin D.