What Supplements Should You Take on Ozempic? A Practical 2026 Guide

If you are taking Ozempic, Wegovy, Mounjaro, or another GLP-1 medication, you have probably noticed the obvious thing: you eat a lot less. That is the point of the drug, and it works. But there is a quieter consequence that gets less attention. When your total food intake drops, your intake of vitamins, minerals, and protein drops right alongside it. The question of what supplements to take on Ozempic is really a question about filling the gaps that a smaller appetite leaves behind.

This guide walks through why those gaps happen, which nutrients the 2026 research flags as most at risk, what to actually consider adding, and how to be smart about timing so you are not making side effects worse. None of this replaces bloodwork or your prescriber's advice, but it gives you a practical framework to bring to that conversation.

Why do GLP-1 medications create nutrient gaps?

GLP-1 medications create nutrient gaps mainly through one simple mechanism: you eat less, so you take in less of everything. These drugs slow gastric emptying and blunt appetite, which is exactly why they help with weight loss. But the body still needs the same baseline of vitamins, minerals, and protein it always did, and a much smaller plate makes hitting those baselines harder.

There is a second, subtler factor. Slowed digestion and the appetite shift can change what foods feel tolerable. Many people on GLP-1s drift toward smaller, simpler meals and away from the nutrient-dense variety they used to eat. Over months, a narrower diet plus a smaller total volume can add up to real shortfalls even in someone who looks like they are doing everything right.

This is different from a drug like metformin, which interferes with absorption directly. GLP-1s mostly work through intake, not absorption. That distinction matters because it means the fix is largely about planning your reduced food intake and supplementing deliberately, rather than fighting a blocked pathway.

Which deficiencies does the 2026 research actually flag?

Two large 2026 analyses of GLP-1 users identified a consistent short list of nutrients that trend low. These are the ones worth putting on your radar and, ideally, testing for.

• Vitamin D. The most commonly flagged gap, with deficiency observed in a meaningful share of GLP-1 users. Vitamin D supports bone, immune, and muscle function, and low levels are already widespread in the general population before any medication.
• Vitamin B12. Important for energy, nerve function, and red blood cell production. Lower food intake, especially reduced animal products, can pull B12 down over time.
• Iron. Reduced intake of iron-rich foods can lower iron stores. Fatigue and low energy are easy to blame on the diet itself, when iron may be part of the picture.
• Magnesium. Involved in hundreds of processes including sleep, muscle function, and energy. Easy to underconsume on a smaller diet.
• Zinc. Supports immune function, taste, and wound healing. Notably, low zinc can dull taste further, which can worsen the appetite loss in a frustrating loop.

The through-line is that none of these are exotic. They are the everyday nutrients that a full, varied diet normally covers without thought, and that a reduced diet can quietly let slip.

What should you actually consider taking?

Here is the practical framework. Think of it in tiers, from the things almost everyone on a GLP-1 benefits from considering, down to the targeted fixes that depend on your labs.

• Protein first. This is the single most important one, and it is not technically a vitamin. Rapid weight loss on GLP-1s can include muscle loss, and protein is what protects against it. Aim for a consistent daily target, often cited around 0.7 to 1 gram per pound of goal body weight, and use a clean protein shake to close the gap on low-appetite days.
• A foundational multivitamin. A simple insurance policy against the broad, mild shortfalls that come with eating less. It will not fix a real deficiency, but it covers the small everyday gaps.
• Vitamin D, tested. Given how commonly it runs low, this is often the first targeted addition, but dose it based on a blood level rather than guessing.
• B12, iron, magnesium, and zinc as your labs direct. These are the test-and-treat nutrients. Do not stack all of them blindly. Iron in particular should only be supplemented if you are actually low, since excess iron is not benign.
• Hydration and electrolytes. Reduced intake plus any nausea or GI changes can leave you underhydrated. A basic electrolyte approach can help with the fatigue and headaches some people report.

The honest answer to what to take is: protein and a foundational multivitamin for almost everyone, then vitamin D and the rest guided by bloodwork. Test, do not guess.

Which supplements should you be cautious with on GLP-1s?

Some supplements can amplify the side effects GLP-1 users already deal with, so timing and form matter as much as the choice itself. The main issues come from the slowed digestion and the GI sensitivity these drugs can cause.

• High-dose magnesium citrate has a laxative effect. If you already have loose stools, magnesium glycinate is a gentler form. See our guide on magnesium glycinate vs citrate for the difference.
• Large iron doses are notorious for nausea and constipation, both of which overlap with common GLP-1 side effects. Only supplement iron if you are confirmed low, and take it with food or as directed.
• Bulky fiber supplements and large pills can sit heavily when your stomach is emptying slowly. Introduce fiber gradually and with plenty of water.
• Anything new, all at once. Adding several supplements the same week makes it impossible to tell what caused a stomach upset. Introduce one at a time.

A good general rule is to take supplements with a small amount of food and space them out rather than dosing everything at once on an empty, slow-emptying stomach.

How to actually track this (the Flexwell tie-in)

The tricky part of supplementing on a GLP-1 is that the effects are slow and easy to miss by feel. You cannot tell whether your vitamin D is climbing back into range, whether you are actually hitting your protein target most days, or whether that new magnesium is the reason your sleep shifted. Memory is a poor instrument for something that plays out over months.

Flexwell is built for exactly this. Log your GLP-1 medication alongside your supplements in one stack, and Flexwell flags known interactions and depletion notes so nothing quietly slips through. Set reminders so the supplements you meant to take actually get taken on low-energy days, and track your protein intake so you can see whether you are truly hitting the target or just assuming you are. Connect your Apple Watch or Oura Ring and Flexwell will surface energy, sleep, and recovery trends over time, which can be an early soft signal worth mentioning to your doctor before your next blood panel. If you are layering several new supplements, our guide to supplements you shouldn't take together covers the timing basics.

For GLP-1 users specifically, this turns a vague sense of "am I covering my bases" into something you can actually see.

The bottom line

The supplements to take on Ozempic come down to a simple logic: you are eating less, so plan to fill the gaps. Prioritize protein to protect muscle during weight loss, add a foundational multivitamin, and use bloodwork to guide targeted vitamin D, B12, iron, magnesium, and zinc rather than guessing. Be cautious with forms and doses that can worsen GI side effects, introduce things one at a time, and take them with a little food. Most importantly, track what you take and how you feel, because the whole challenge of GLP-1 nutrition is that it unfolds too slowly to notice without a record. Bring your list and your labs to your prescriber and build the plan together.

Flexwell is a wellness tracking tool and does not provide medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making changes to your supplements or medications.