Weight-loss injections – what should I consider with a vegan diet?

GLP-1 stands for glucagon-like peptide-1. It is an endogenous hormone that is involved, among other things, in the regulation of blood sugar, appetite and satiety.

GLP-1 is mainly released in the intestine after eating. It promotes insulin release and inhibits glucagon secretion at normal and elevated blood sugar levels, while this effect decreases at low blood sugar levels. As a result, less glucose enters the bloodstream from the liver and the blood sugar level remains stable. This effect is particularly relevant for people with diabetes.

In addition, GLP-1 slows gastric emptying and influences hunger and satiety via the central nervous system. GLP-1 receptor agonists can therefore reduce food intake because the feeling of satiety lasts longer and appetite is reduced.

Simply put: GLP-1 sends the brain the signal “You are full”, which can reduce food intake.

The term “weight-loss injections” refers to various prescription medications that are used for the treatment of obesity. Many of the active substances used today were originally developed for the treatment of type 2 diabetes. These include, among others, GLP-1 receptor agonists, which bind to the GLP-1 receptor and thereby mimic the effect of the body’s own hormone.

GLP-1 receptor agonists can therefore slow gastric emptying, reduce appetite and increase the feeling of satiety. As a result, food intake may decrease and weight loss can be supported. Some of the active substances used today act longer than the body’s own GLP-1 and thus provide a longer-lasting effect. Well-known active substances include, for example, semaglutide (Wegovy) and liraglutide (Saxenda).

Depending on the active substance and preparation, the medications are administered by injection in different dosages and intervals. The dosage is usually adjusted gradually and should be medically supervised.

Obesity is a chronic disease characterised by an excessive accumulation of body fat. The body mass index (BMI) is used for classification. It is calculated as body weight in kilograms divided by the square of height in metres (kg/m²).

• Overweight in adults: BMI ≥ 25
• Obesity in adults: BMI ≥ 30

Overweight and especially obesity can be associated with an increased risk of various secondary diseases, including, for example, type 2 diabetes and cardiovascular diseases.

Due to the significantly reduced appetite, an adequate supply of energy and important nutrients can be challenging. Especially with a vegan diet, it is therefore worth taking a closer look at the composition of meals.

When less food is eaten overall, it can become more difficult to meet the need for certain micronutrients. That is why the quality of foods is particularly important during weight loss.

A varied vegan diet should contain as many nutrient-rich foods as possible – for example vegetables, fruit, legumes, wholegrain products, nuts and seeds.

Depending on individual needs, food supplements may be useful. One option is multi-nutrient preparations, such as our nutri+ Vegan Essentials capsules or our nutri+ Vegan Essentials powder, which contain an optimal combination of different vitamins and minerals.*

During weight loss, important muscle mass can be lost in addition to body fat. Therefore, in addition to weight loss, muscle maintenance should also be taken into account.

Protein is particularly important here, because proteins contribute to the maintenance and growth of muscle mass . In addition to sufficient protein intake, strength training plays an important role.

With a vegan diet, legumes, soy products such as tofu and tempeh, seitan, nuts, seeds and protein-rich grain products, for example, provide valuable plant-based proteins.

Vegan protein powders, such as our 3K or 6K protein powders with over 20 flavours, can also be a practical way to support daily protein intake – especially when larger meals are difficult due to reduced appetite.

GLP-1-based medications can cause side effects such as nausea, vomiting, diarrhoea, constipation and a feeling of fullness. This can further reduce appetite. If less food is eaten overall, fibre intake may also be lower.

Especially then, it is worth paying attention to sufficient fibre intake. Fibre supports a normal bowel function. Among other things, it influences the transit time of food as well as the bulk and consistency of stool.

The DGE (German Nutrition Society) recommends that adults consume at least 30 g of fibre per day. Fibre-rich foods include, for example, wholegrain products, legumes, vegetables, fruit, nuts and seeds.

If your diet has previously been low in fibre, intake should not be increased significantly all at once. A gradual increase and sufficient fluid intake can improve tolerability.

GLP-1 medications influence various metabolic processes. In addition, reduced energy intake can be associated with fatigue or exhaustion, especially at the beginning of treatment.

Various B vitamins and other micronutrients are required for a normal energy metabolism. Chromium also plays an important role in metabolism. The essential trace element contributes to the maintenance of blood sugar levels and to normal macronutrient metabolism.

To combine all important micronutrients in one product, we developed our nutri+ Stoffwechsel Aktiv. It supports metabolism with ten vitamins, three minerals, various plant extracts and coenzyme Q10.*

A balanced, calorie-reduced diet as well as regular exercise and sport – ideally a combination of strength and endurance training – are important components of the therapy.

For a vegan diet, this means, for example:

Important: Anyone who does not also change their lifestyle in the long term may gain weight again after therapy.

A weight-loss injection is not the right choice for everyone. Whether a GLP-1-based medication is suitable depends, among other things, on your BMI, possible accompanying diseases, previous measures and your health situation .

A balanced diet and regular exercise remain the most important components of long-term weight loss. Even small changes in everyday life can make a big difference.

In addition, our nutri+ Glucomannan capsules can be a practical supplement.* Glucomannan contributes to weight loss as part of an energy-restricted diet. The beneficial effect is obtained with a daily intake of 3 g glucomannan in three portions of 1 g each, together with 1–2 glasses of water before meals. You can read more about this in our blog post “What is glucomannan? Intake, effect & side effects”.

*Note: Food supplements are not a substitute for a balanced and varied diet and a healthy lifestyle.

• Xie, Y., Choi, T. & Al-Aly, Z. (2025): Mapping the effectiveness and risks of GLP-1 receptor agonists. Nature Medicine, 31, 951–962.
• Drucker, D. J. (2018): Mechanisms of Action and Therapeutic Application of Glucagon-like Peptide-1. Cell Metabolism, 27(4), 740–756.
• German Nutrition Society (DGE): Overweight and obesity. German Nutrition Society: Overweight and obesity
• Robert Koch Institute (RKI): Obesity and overweight. Federal Health Reporting. RKI Federal Health Reporting
• European Commission (2012): Commission Regulation (EU) No 432/2012 of 16 May 2012 establishing a list of permitted other health claims made on foods. Official Journal of the European Union, L 136, 25.05.2012, p. 1–40. EUR-Lex Regulation (EU) No 432/2012