Taking GLP-1 drugs? 5 Things you should know
Disclaimer: First, if you’re taking any weight-loss medication, always consult your healthcare provider before making any changes to your diet.
1.GLP-1 drugs are here to stay, whether some people like it or not.
Why do I say this? Maybe it is just me, but I get the sense that some health professionals feel threatened by them (perhaps because widespread use could mean fewer clients needing their services). I do not agree with that reasoning. Then there are those who dismiss GLP-1 users as simply taking the easy way out, as if weight loss must come with struggle. Eye roll…
But that is not what this article is about. This is for those who are taking GLP-1 drugs or planning to in the future. These medications come with complexities, and there are important things you need to know. I am also excited to share some new drug developments with you.
Yes, weight-loss drugs are here to stay. In fact, more than 100 new anti-obesity drug candidates are currently in development ¹, many of which target multiple biological pathways to enhance weight loss while reducing side effects. Progress is moving fast. Not all of these drugs focus solely on GLP-1 mechanisms: some target other pathways, such as cannabinoid receptor blockers (like Monlunabant), Amylin, and GIP (Glucose-Dependent Insulinotropic Polypeptide).
A new weight-loss drug, MariTide, could be available by 2028. Unlike semaglutide and tirzepatide, which sometimes lead to weight regain after discontinuation, MariTide may help people maintain their weight loss even after stopping the medication².
Benefits versus risks of GLP-1RAs, based on ‘‘Why do obesity drugs seem to treat so many other ailments?’’ and ‘‘Mapping the effectiveness and risks of GLP-1 receptor agonists’’.
2. GLP-1 and Muscle Loss: What science is doing about It
Let’s talk about the well-known concern of muscle mass loss. There is a lot of discussion about GLP-1 drugs causing muscle loss, and these concerns are valid: up to one-third of the weight lost with current obesity drugs comes from muscle¹, which can impact metabolism, mobility, and long-term health.
But if you look at the available research, any significant weight-loss intervention can lead to muscle loss. Bariatric surgery? Yes. Aggressive calorie deficits? Absolutely. This is not something unique to GLP-1 drugs. The more weight you lose, especially at a rapid pace, the higher the risk of losing muscle, no matter the method³ ⁴ ⁵ ⁶. Strength also tends to decrease after weight loss ⁷ ⁸.
Now for some good news. Eli Lilly (a pharmaceutical company) is currently conducting a study on a combination of tirzepatide (a GLP-1 receptor agonist) and Bimagrumab.
Bimagrumab is an interesting drug that I only learned about a few days ago (which led me to write this article). It works by blocking a protein that limits muscle growth, making it a potential solution to counteract the muscle loss sometimes seen with GLP-1 medications. It is a fascinating drug, and I imagine the gym bros are thrilled, though I am not sure it is aimed at them…
And that’s not all. Looking at the trials they are enrolling for, Eli Lilly is also researching orforglipron (another GLP-1) in pill form. They are comparing tablets versus capsules. Are you thinking what I’m thinking? No more needles at all? Science, you’re a rockstar!
3. How to counteract muscle loss when using GLP-1-like drugs
Ever heard of sarcopenia? It's the loss of muscle mass and strength, and it can lead to weakness, mobility problems, and a higher risk of falls. It's mainly caused by aging, inactivity, and not eating enough protein. (And don't worry, it's not directly caused by weight loss drugs...yet, so no need to panic). Sarcopenia is common after 65 and in the elderly, as well as in people with muscle-wasting diseases ¹².
But why am I bringing this up now? Well, what you do now, when you're younger, impacts whether you develop sarcopenia later in life.
Muscle mass is so important. It's crucial for metabolic health, mobility, strength, blood sugar and insulin sensitivity, supporting bone density, and reducing the risk of osteoporosis¹³ ¹⁴. Plus, muscles are like awesome little carb banks, storing glycogen (aka carbs) from that croissant you enjoyed. Plus, muscles look great too.
So I’ll try keep this short and sweet (something I'm terrible at):
Here’s how you can counteract muscle loss if you’re following a drastic weight loss program or taking GLP-1 drugs:
Prioritize protein: High-quality protein is essential for muscle repair and growth. Aim for at least 1.6-2.0g per kg of body weight daily.
Use It or Lose It: This applies to everyone, not just GLP-1 users. You need strength training/resistance training 3–5 times a week to build and maintain muscle.
Recovery is as important: Recovery is just as important. Get enough sleep, eat well, and maybe don’t drown yourself in alcohol: yada yada, boring, I know, but it matters. Muscle recovery happens during rest, so take your rest days seriously and aim for at least 7 hours of sleep per night
Don't overdo the deficit: An extreme calorie deficit can mean extreme muscle loss. A moderate calorie deficit is best for fat loss while preserving muscle in time.
If struggling with protein intake, consider whey, casein or soy protein shakes in between your meals or as a snack ¹⁰.
Carbs are very important for recovery as well, don’t ignore them!
Supplements (ask your doctor first): Creatine is a supplement that could help with lifting weights (more power) and improving muscle strength ⁹ . And It's backed by science. For muscle soreness, consider branched-chain amino acids (BCAAs). They may help ¹¹.
Spread it out: If you're eating a lot of protein, distribute your intake evenly across meals to maximize muscle protein synthesis throughout the day¹⁵.
Well, that’s all. Now go lift something heavy, eat loads of protein and sleep well!
4. Weight Loss, Osteopenia, and Bone Loss: Are there any risks?
We talked about sarcopenia, but have you heard of osteopenia? As someone fairly young (hey, I’m in my early 30s), I had heard of it, but it hit differently when I found out my own bone mineral density was on the lower side during a DEXA scan. That was scary to hear.
For me and for many women, the risk is even higher because of menopause and declining estrogen levels, which reduce calcium absorption ¹⁶ ²⁴. Not fun, right? But don’t despair! There is a lot you can do about it, and we’ll get to that soon.
So why am I telling you this? First, because osteopenia is a serious concern. It means your bones are weaker than normal but not weak enough to be classified as osteoporosis (hope I’m not butchering WHO’s definition here). In simple terms, your bones have a lower mineral content than they should, putting you at a much higher risk of fractures and osteoporosis later in life.
And bone fractures? They are linked to a high mortality risk. A hip fracture can mean surgery, immobility, and serious complications. Studies show that within a year of experiencing a hip fracture, 18% to 33% of older adults may die ²². Crazy, I know.
Now, here’s something else you should know: weight loss and bone density loss are connected. Multiple meta-analyses (large studies reviewing multiple trials) show that weight loss can contribute to bone loss ¹⁷ ¹⁸ ¹⁹ ²⁰ ²¹. Women may be even more prone to this because of menopause.
So here are few strategies on how to counteract bone loss:
Exercise: Of course, I was going to say this. Isn't exercise the panacea for everything? For bone density, focus on weight-bearing exercises like lifting weights, jumping, running, and whole-body vibration exercises that stimulate bone formation. Walking with a weighted vest might help as well. Balance exercises are also important for mobility and reducing the risk of falls ²³.
Calcium & Vitamin D: Prioritize calcium-rich foods and supplement with vitamin D in the winter if you don’t get enough sun exposure.
Minerals & polyphenols : a diet rich in phosphorus, magnesium, potassium, sodium, zinc, selenium, copper, vitamins C and K supports bone health²⁵.
Reduce Alcohol & Smoking: Both are directly linked to weaker bones and higher fracture risk ²⁶ ²⁷.
Check your bone density : A DEXA scan will show where you stand. Knowing your bone health status might help in taking action early.
Build muscle: Strong muscles support mobility and stability, reducing the risk of falls and fractures²⁸. Strength training is going to be your best friend.
Eat more protein: A high-protein diet supports both muscle and bone health ²⁹ .
Take care of your hormones: Regular hormonal checks can help you spot issues like declining estrogen or testosterone, both of which impact bone density³⁰.
Collagen intake: The evidence on its benefits isn’t conclusive, some studies show benefits, some don’t. For example this study suggests that taking 5 grams of collagen peptides daily may help improve bone density mass (BMD) in postmenopausal women.
Type 1 collagen plays a role in bone cell formation³¹. You’ll find it in marine collagen, bone broth, beef tendons, and gelatin.
5. Nutritional Deficiencies and GLP-1 Use
We know GLP-1 drugs work by reducing appetite, but they can also cause side effects like nausea and gastrointestinal issues, leading to reduced food intake.
This means that when you do eat, you need to be intentional about getting enough nutrients to support your body, counteract muscle and bone loss, and prevent nutritional deficiencies.
Based on the available research I could find so far ³² ³³ ³⁴ ³⁵ ³⁶, here are my recommendations for those taking GLP-1 drugs, other weight-loss medications, or simply losing weight in general:
1.Protein
Muscle loss is a real concern: studies suggest that 15–60% of total weight lost may come from lean body mass ³⁷ when using GLP-1RA drugs, which isn’t ideal. I actually find this a bit shocking. So, if someone lost 100 pounds, the estimated muscle mass loss could be anywhere between 15 and 60 pounds, depending on factors like protein intake, resistance training, and their nutrition. Crazy! I wouldn’t want to lose my precious muscle mass when it’s so hard to build in the first place
To help prevent this:
Aim for at least 1.5-2 g of protein per kg of body weight to support muscle retention and metabolism.
Prioritize lean meats, legumes (beans and lentils), and protein supplements if needed.
Distribute protein intake evenly throughout the day for better absorption and muscle maintenance.
Make lifting weights your new best friend.
2.Fiber & Hydration
Since constipation is a common side effect of weight-loss drugs:
Ensure adequate fiber intake to support digestion and gut health.
Stay hydrated, water is key for digestion and metabolic function.
Fiber also helps feed beneficial gut bacteria.
3.Micronutrients
Deficiencies in vitamin D, B12, calcium, iron, and zinc are common in people with obesity and may worsen with lower food intake.
A multivitamin with minerals may be beneficial (as always, ask your doctor first).
Many people already have low intakes of vitamin D, calcium, iron, fiber, and potassium, weight loss can further increase the risk of deficiencies.
4.Meal Replacements
For those struggling with appetite, meal replacements can help ensure adequate nutrient intake.
5.Nutrient-Dense Foods
Since you can’t eat large quantities, prioritizing nutrient-dense foods is essential:
Focus on fruits, vegetables, whole grains, lean proteins, and healthy fats.
Final Thoughts
I fully support GLP-1 medications, and honestly, I don’t understand why some people are so against them. They do far more than just aid in weight loss: they can improve type 2 diabetes, sleep apnea, atherosclerosis, PCOS, inflammation, fatty liver disease, cognitive health, and even addiction and cravings. Yes, there are potential downsides, like muscle and bone loss, but (1) you can take steps to counteract this (as discussed in this article), and (2) the benefits far outweigh the risks.
For my fellow health practitioners: we have a role in reducing the stigma around these medications. Do not make it worse by scaremongering about the risks. Most can be managed with proper guidance, including appropriate exercise and nutrition.
Aaand that’s all for now! I hope this was helpful!
P.S. If you need a nutritionist to help you with your health goals, I’d love to help!
I look forward to helping you thrive!
M.
Curious to learn more ? Check out other articles on the blog for tips, myths, and science-backed insights:
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