Energy, hair, the shape of my arms. When you eat 30 to 50% less food, you're not just cutting calories. You're cutting nutrients too. Here are 8 things I wish I'd understood sooner, and the simplest move I made because of them.
This is the whole thing in one line. When the portions shrink, everything in the food shrinks with them, protein, iron, calcium, B12, magnesium, the lot.
A 2025 review in Frontiers in Nutrition found people on GLP-1 medications were coming up short on fiber, calcium, iron, magnesium, potassium and several vitamins. You can lose weight and run low at the same time. That was the realization that started all of this for me.
I kept calling it "tired" but it was deeper than tired. Flat. No fuel.
Dietitians who work with GLP-1 patients say it plainly: when you're eating half of what you used to, low energy is one of the first things they look at, because the body is simply getting less to run on. It's not a mystery and it's not a moral failing. It tracks with the intake.
Mine started shedding a few months in. Enough to notice in the drain. Enough to mention to my doctor.
Rapid weight loss and low protein and nutrient intake are both well-documented contributors to this kind of shedding, and the FDA has logged hundreds of hair-loss reports tied to these medications. I'm not telling you a powder undoes that. I'm telling you that when I learned the link ran through nutrition, "am I actually feeding myself?" stopped being a vague worry and became a real question.
This is the one I didn't see coming. A joint advisory from four major medical and obesity organizations reported that in one major trial, of the average weight lost, about 38% was lean mass, not fat.
Their guidance wasn't "stop the drug." It was that nutrition, especially enough protein and the nutrients that support the body, matters more while you're eating less, not less. Muscle is the thing under the number on the scale. It's worth protecting.
"Every bite has to count."
A registered dietitian at UCHealth put it exactly that way: when patients are eating roughly half of what they did, every bite needs to be nutritious because there's so little room for filler. A physician at Harvard Health went further and suggested people on these medications consider a daily multivitamin, naming vitamin D, iron and B vitamins specifically. When Harvard and your dietitian land in the same place, you listen.
So I bought a multivitamin, like the Harvard piece said. Good first step. But a multivitamin is a handful of isolated vitamins in a pill.
What I actually wanted was a daily nutritional base, something closer to food than to a vitamin tablet, that covered more than a dozen lines on a label. That's a different category, and it's where I landed next.
I didn't want another routine. On a day I'm forcing myself to eat, the last thing I need is five more bottles.
AG1 is one scoop in a glass of water, a whole-food-based daily foundation with 75 ingredients, and it's clinically shown to close common nutrient gaps. I drink it alongside my protein, not instead of it. It's the cold glass I can manage on a morning when solid food isn't appealing. One scoop, once a day, no pills, no clutter. That's the entire reason it stuck.
I'll say it again because it matters. AG1 is food-based daily nutrition. It is not a drug, it doesn't replace your medication, your protein, or your doctor's plan, and you should run anything new past the person who prescribed yours.
What it does is simple and worth doing: it helps cover the nutritional base your body still needs on the days you're eating a fraction of what you used to. For me that was the missing piece. For you, your doctor will know.
AG1 doesn't claim to treat any of this. It's a daily nutritional foundation, clinically shown to close common nutrient gaps, that you can lean on while you're eating less.
$79 a month on subscription, about $2.63 a day. The first order includes the welcome kit: travel packs, vitamin D3+K2 drops, a canister and a shaker. Cancel anytime.
One scoop, once a day
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It's a scoop of powder in water you sip, not a meal to get through. A lot of people find a cold glass easier than solid food when appetite is low.
AG1 is food-based daily nutrition, not a drug. But anything you add while on a prescription should be cleared with your prescribing doctor or pharmacist first. Please do that.
A multivitamin is isolated vitamins. AG1 is a whole-food-based foundation of 75 ingredients, clinically shown to close common nutrient gaps. Different breadth, different format.
No. Protein is its own priority while you're losing weight. Think of AG1 as the daily nutritional base alongside your protein, not a swap for it.
$79 a month on subscription, roughly $2.63 a day, with a welcome kit on the first order.
If you're eating a fraction of what you used to and you've noticed the energy, the hair, the softness, the nutrition underneath is worth a real look. One scoop a day covers a lot of base. Run it past your doctor, then decide.
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