01
Rapid loss can include lean mass
Weight loss does not only come from body fat. Some of it can come from the muscle that supports your strength, shape and metabolism.
After months of forcing down shakes she couldn't finish, Amber built the protein for a smaller appetite.
The protein you finish is the only protein that counts.
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Why this matters now
01
Weight loss does not only come from body fat. Some of it can come from the muscle that supports your strength, shape and metabolism.
02
Lean mass does not simply return on its own. Rebuilding it usually requires consistent protein intake and resistance training.
03
Supporting strength from the beginning is easier than waiting until weakness or changes in body composition become noticeable.
Thirty grams left in the cupboard is still zero grams. Mainstay was designed around a smaller serving you are more likely to keep drinking.
Why it's different
Most protein products were built around bigger servings and bigger appetites. Mainstay was designed to feel lighter and easier to keep using.
Mainstay
Texture
Clear and refreshing, more like juice
Serving
One small, manageable glass
Routine fit
Easy to sip on lower-appetite days
Added support
Protein, fibre and electrolytes together
Consistency
Built around what you can realistically finish
Traditional protein
Texture
Often thick, milky or chalky
Serving
Large shake or heaped scoop
Routine fit
Can feel like another meal to get through
Added support
Usually focused on protein alone
Consistency
Easy to abandon when appetite is low
Mainstay is not trying to be the largest protein serving. It is designed to be the one that fits into the routine you actually have.
Formulated specifically for GLP-1 users to support muscle maintenance, strength, and daily protein intake — helping your body adapt to weight loss without losing lean mass.
Protein gives your body the raw material. Creatine helps you keep it. And a routine you can actually stick to is what makes both of them count.
The Clear Refresher — 10g of complete protein in a light, cold glass you'll actually get down on your worst appetite day.
5g a day, as a gummy. The most-studied strength ingredient there is — it quietly helps you hold on to muscle. Free with the 3‑month protocol.
One scoop, cold water, done. No blender, no shaker, no cleanup. The protocol only works if you actually do it — so we built it to take less effort than making coffee.
One of the benefits of GLP-1 medications is that they slow gastric emptying, making you less hungry overall. But if you don’t change your eating habits, you’re more likely to suffer from side effects like nausea, constipation, diarrhea, or vomiting because of this reason.
To avoid GI distress while taking a GLP-1 medication, you’ll need to reduce the volume of food you eat to avoid feeling uncomfortably full or dealing with an upset digestive system.
This is different from traditional dieting advice, which tells you to fill up on high-density, low-volume foods. On GLP-1 medications, the goal is not to “fill up” in the same way since the medication is slowing your digestive system down.
Don’t get me wrong, fruits and vegetables are great. But for anyone getting used to being on a GLP-1 medication, getting enough calories from nutrient-dense sources is important and can be more difficult.
That’s why anyone on a GLP-1 medication should first focus on protein, which packs a bigger nutritional punch without overloading your digestive system.We created Mainstay to make it easy for GLP-1 users to quickly and easily fuel up with the protein they need. Unlike other protein powders, it’s SUPER gentle on the gut: made with lactose-free whey protein isolate and enhanced with digestive enzymes that kick in quickly and help your system digest your food for up to 24 hours. The best part? It’s less than 3g of carbs and won’t spike blood sugar.
Mix one scoop into cold water — more water if you want it lighter. It comes out clear and juice-like, not creamy. Most people have it in the morning. Thirty seconds, done.
It's a food supplement designed to sit alongside your routine, not replace anything. As with any supplement, run the ingredient list past your prescriber or pharmacist if you have questions — especially with kidney conditions or a complex medication list.
Once your order ships, you'll receive a tracking number via email. You can use this to track your package on our website or the carrier's site.