Bloodworks
Weight Loss & Metabolism7 min read·

GLP-1, Ozempic, and medical weight loss: what can you have tested?

GLP-1 agonists such as semaglutide are very much in the spotlight. But those who use them, or are considering doing so, benefit from insight into a number of blood values. What you need to know.

What are GLP-1 agonists?

GLP-1 stands for glucagon-like peptide-1, a hormone the body produces naturally after a meal. It suppresses appetite, slows gastric emptying, and stimulates insulin release. GLP-1 agonists are medications that mimic this hormone. The best known is semaglutide, under the brand names Ozempic (for type 2 diabetes) and Wegovy (for weight management). Tirzepatide (Mounjaro) works on a similar principle but targets two hormone receptors.

These medications were originally developed for type 2 diabetes. The weight loss that occurred with use was so significant that they are now also used outside diabetes treatment, in the Netherlands through a limited number of clinics and an increasing number of online providers.

Why is blood testing relevant with GLP-1 use?

GLP-1 medications influence metabolism on multiple fronts. With use, blood glucose, insulin sensitivity, and sometimes liver function change. Those who already have an increased risk of metabolic problems, think insulin resistance, fatty liver, or abnormal liver enzyme levels, would do well to map that picture before and during use.

Responsible use of GLP-1 medications begins with a good baseline profile. That way you know what is changing, and whether that change is in the right direction.

Which blood values are relevant?

The most relevant markers in medical weight loss and GLP-1 use are: fasting blood glucose and HbA1c (sugar metabolism), liver enzyme levels ALAT and ASAT (liver function), kidney function (creatinine, eGFR), lipid profile (cholesterol, triglycerides, HDL, LDL), and insulin or C-peptide for those wishing to assess insulin resistance.

In addition, there are markers that are indirectly relevant with significant weight loss: ferritin (iron stores can fall with reduced intake), vitamin D, vitamin B12, and folic acid. Those who eat little also take in fewer micronutrients.

Want to have a baseline measurement done?

The Medical Weight Loss & GLP-1 package measures HbA1c, cholesterol, liver enzymes, ferritin, B12, and vitamin D in a single blood draw.

View package · €179 →

Fasting or not fasting?

For a complete metabolic profile, including fasting glucose, insulin, and triglycerides, fasting blood draw is necessary. Fasting means at least twelve hours without food, water only. Bloodworks schedules blood draws early in the morning, so fasting is practical without disrupting your day.

What does a responsible programme look like?

Those who seriously want to lose weight with medical support begin with a baseline measurement before starting. A repeat measurement after three to six months is then worthwhile: have blood sugar values improved? How is the liver doing? Have any deficiencies developed? That data gives direction for next steps, regardless of whether you are taking medication or not.

Bloodworks does not carry out medical treatments and does not prescribe medication. We provide insight into your blood values, with interpretation by BIG-registered doctors. You can share that insight with the doctor or clinic supervising your treatment.

Have it tested at Bloodworks

Medical Weight Loss & GLP-1 · €179

HbA1c, cholesterol, liver enzymes, ferritin, vitamin B12, and vitamin D, 6 markers in a single blood draw with personal doctor interpretation.

View package and order →

Or build your own package with exactly the markers you need

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