I get asked all the time what I think about these newly popular weight-loss drugs, variously known as GLP-1 receptor agonists (for their effects) or semaglutides (for the active ingredient in the most widely used drugs).
Here’s the thing: taking them is probably better than being obese. I obviously prefer using diet and training and lifestyle modifications to deal with obesity, but if a person wants to take these drugs, and is willing to take them for life, then take the drugs. The research is quite clear that in such situations these drugs improve health.
The big issue with weight loss from GLP-1 drugs is that it doesn’t require you to change anything. If you lose weight via conventional means, you’re lifting weights, going on walks, eating more protein-rich foods, and eliminating processed junk food. These are all things that build muscle and drop body fat, that improve nutrient partitioning and body composition. With GLP drugs, you don’t have to lift weights or change what you eat. The drugs take over and do it for you.
So if you’re going to take these GLP-1 drugs, here’s what I recommend:
Prioritize protein.
You simply have to eat protein. Your overall calorie intake is going to drop by an incredible amount. Food itself won’t be very appetizing, and you’ll get satiated on far less than normal. Make sure you’re still hitting 100-120 grams of high-quality protein per day at a minimum.
One of the biggest side effects of weight loss with the GLP-1 agonist drugs is muscle loss. I don't put stock in the animal studies that show evidence for increased muscle function and mitochondrial density with these drugs. That may be true, but the fact remains that human studies consistently show that muscle loss occurs to a greater degree than losing weight with a low-carb, high-protein diet.
Take whey isolate.
This is where whey protein isolate can come in. 20-40 grams of that per day slipped into a shake, your iced coffee, water—anything that allows you to drop it quickly down the hatch—will help stave off muscle loss. It’s a lot easier to swallow 20 grams of whey isolate in some water than it is to eat a few ounces of lean steak when you aren’t hungry at all.
Lift heavy things.
I would keep weights heavier and sets shorter. You don’t want to force yourself to expend a ton of energy, burning through everything and making it harder to recover. You’re not trying to gain muscle or burn calories (that’s what the drugs are for). You’re just sending the message to your body that your lean mass is still useful and you need to hold onto it even as calorie intake drops.
The more intense the weights, the stronger the message.
Stay active in general.
I’ve seen research showing that people who exercise and lift weights and generally stay active while taking the GLP-1 agonist drugs have better outcomes when they decide to go off them—almost as if you’re sending your body a powerful message of vitality and strength. “I’m not relying on these drugs entirely, I’m still getting after it.”
Don’t ignore the side effects.
Weight loss is great, but there are some potential side effects to watch out for.
Gastroparesis: Gut stasis. Food literally stays longer in your gut without being digested. Signs of this include nausea after eating, vomiting, and constipation. It can be quite serious. Do not ignore.
Elevated resting heart rate: Peter Attia noticed this in many of his patients taking the GLP-1 drugs. It may not happen, but be aware of the possibility.
Anhedonia: GLP-1 drugs tend to lower dopamine levels, which can help make food (and drugs, and alcohol, and other addictive habits) less rewarding and pleasurable—but it can also make the world seem duller. If everything is less rewarding, the good and the bad, it can trigger a feeling called anhedonia, which is the absence of pleasure. If you find your daily experience of the world becoming flat, consider lowering the dose.
Once again, I’m not totally against these weight-loss drugs. They can definitely help people, and they absolutely “work.” Just understand that the mechanism responsible for their utility in fat loss can have other unwanted effects, too.
