Weight-loss drugs like semaglutide linked to severe nutrient deficiencies in long-term users

Weight-loss injections like semaglutide and tirzepatide may carry hidden risks for long-term users. A review of nearly 481,000 participants across six clinical trials has revealed widespread nutrient deficiencies among those taking these drugs. Experts now warn that patients could face malnutrition, muscle loss, and other health complications without proper monitoring.

The drugs, known as GLP-1 receptor agonists, work by suppressing appetite, leading to reduced food intake. However, this effect has been linked to serious nutritional gaps. Over 60% of users consumed less calcium and iron than recommended, while vitamin D intake averaged just 20% of the required amount.

Recent European studies (2024–2026) show that vitamin D deficiency rates among users have climbed to 30–40% in some groups. Elderly patients, those with limited sun exposure, and individuals with darker skin in northern Europe appear most affected. Control groups, by comparison, had deficiency rates of only 20–25%.

The consequences extend beyond vitamins. Protein and calcium shortages contributed to muscle loss, while thiamine and cobalamin deficiencies worsened over time. Iron levels also dropped sharply, with ferritin measurements in GLP-1 users falling 26–30% below those in patients on other diabetes medications. One study found that 38% of weight-loss drug users showed signs of malnutrition—far higher than the 9% seen in non-users.

Beyond nutrient deficiencies, these injections may also reduce thirst, raising dehydration risks. Medical professionals now urge dietary counselling for all patients prescribed these treatments.

The findings highlight the need for closer monitoring of patients on GLP-1 receptor agonists. Without intervention, long-term use could lead to persistent malnutrition, weakened bones, and muscle deterioration. Doctors recommend regular blood tests and tailored nutrition plans to offset these risks.