Losing weight while taking prednisone is genuinely difficult because the drug changes your metabolism in multiple ways at once. It increases appetite, makes your body resist insulin, redistributes fat to your midsection and face, and causes you to retain fluid. The good news: targeted changes to your diet, activity level, and eating habits can counter each of these effects, even if you can’t fully prevent them while still on the medication.
Why Prednisone Causes Weight Gain
Prednisone doesn’t just make you hungrier. It fundamentally alters how your body processes food. In studies of healthy young people, even short-term prednisone use reduced the muscles’ ability to absorb glucose by 65% compared to a placebo. That means sugar stays in your bloodstream longer, prompting your body to produce more insulin, which in turn signals your body to store fat. The drug also impairs your body’s ability to break down circulating fatty acids, so fat that would normally be burned for energy gets stored instead.
At the same time, prednisone triggers your body to break down muscle protein while making it harder to build new muscle. Less muscle means a slower resting metabolism, which compounds the weight gain over time. This pattern of losing limb muscle while gaining abdominal fat mirrors what happens in Cushing’s syndrome, a condition caused by chronically elevated stress hormones.
Then there’s fluid retention. Prednisone causes your kidneys to hold onto sodium, which pulls water into your tissues. This can add several pounds that look and feel like fat but are actually water weight. Higher doses taken for longer periods predictably cause more weight gain, though individual responses vary.
Where the Weight Goes
Prednisone doesn’t distribute extra weight evenly. It preferentially deposits fat in your face (sometimes called “moon face”), the back of your neck, and your abdomen, while your arms and legs may actually lose mass due to muscle wasting. A prospective study tracking patients on doses of 20 mg or more daily for three months or longer found that this fat redistribution is common, with women and people who were already overweight before starting the drug at highest risk. This pattern is frustrating because it can make you look like you’ve gained more weight than you actually have, but it also means that some of the visible changes will reverse after you taper off.
Keep Sodium Under 1,500 mg Per Day
Cutting sodium is one of the fastest ways to reduce prednisone-related bloating and puffiness. Published nutritional guidelines for patients on long-term glucocorticoid therapy recommend keeping sodium intake below 1,500 mg per day, which works out to less than half a teaspoon of salt spread across all your meals. That’s stricter than the general recommendation for healthy adults (up to 2,400 mg), and for good reason: prednisone amplifies sodium’s water-retaining effects.
The most practical way to hit this target is to minimize ultra-processed foods, which account for the vast majority of sodium in most people’s diets. Canned soups, deli meats, frozen meals, chips, and restaurant food are the biggest offenders. Cooking at home with fresh ingredients and seasoning with herbs, spices, lemon juice, or vinegar instead of salt makes a noticeable difference within days. You won’t lose fat this way, but you can shed water weight and reduce the puffiness in your face and extremities.
Restructure Your Meals Around Blood Sugar
Because prednisone makes your cells resist insulin so dramatically, keeping your blood sugar stable becomes a priority whether or not you have diabetes. Every time your blood sugar spikes, your body pumps out extra insulin to compensate, and that excess insulin promotes fat storage.
Focus on meals built around protein, non-starchy vegetables, and healthy fats. Think grilled chicken with roasted broccoli and olive oil rather than pasta with bread. When you do eat carbohydrates, choose ones that digest slowly: steel-cut oats, lentils, beans, sweet potatoes, and whole intact grains. Pair them with protein or fat to further blunt the blood sugar response. White bread, sugary drinks, juice, white rice, and sweetened cereals will spike your blood sugar fast and hard, and on prednisone your body is far less equipped to handle that spike.
Eating smaller, more frequent meals rather than two or three large ones can also help keep blood sugar from swinging wildly. Prednisone typically raises blood sugar most in the afternoon and evening (since most people take it in the morning), so being especially careful with carbohydrates at lunch and dinner makes sense.
Managing the Hunger
Prednisone-driven hunger is not regular hunger. It can feel relentless and almost impossible to ignore, which is why willpower alone rarely works. Instead, use the composition of your food to create physical fullness. High-volume, low-calorie foods like leafy greens, cucumbers, celery, broth-based soups, and berries take up space in your stomach without adding many calories. Protein is the most satiating nutrient gram for gram, so front-loading meals with a generous portion of chicken, fish, eggs, Greek yogurt, or tofu can take the edge off.
Fiber is your other ally. Vegetables, legumes, and whole grains slow digestion and keep you feeling full longer. Drinking plenty of water throughout the day also helps, since thirst can masquerade as hunger. Keeping pre-cut vegetables, hard-boiled eggs, or small portions of nuts accessible for snacking means you’re less likely to reach for chips or cookies when the hunger hits.
Prioritize Resistance Training
Exercise matters more on prednisone than it does under normal circumstances, specifically because the drug actively breaks down muscle. Resistance training (bodyweight exercises, weight machines, free weights, resistance bands) directly counteracts this muscle-wasting effect by signaling your body to preserve and rebuild muscle tissue. Since muscle burns more calories at rest than fat does, maintaining muscle mass helps prevent your metabolism from slowing further.
You don’t need to train intensely. Two to four sessions per week focusing on major muscle groups (legs, back, chest, shoulders) is enough to make a meaningful difference. If you’re new to strength training or dealing with joint issues from the condition prednisone is treating, starting with bodyweight movements like squats, wall push-ups, and seated rows with a resistance band is a safe entry point.
Walking and other moderate cardio also help by improving insulin sensitivity, which directly counters one of prednisone’s main metabolic effects. Even 20 to 30 minutes of brisk walking daily can improve your body’s ability to process glucose and burn fat. The combination of regular cardio and resistance training is more effective than either one alone.
Eat Enough Protein to Protect Muscle
Because prednisone accelerates muscle breakdown, your protein needs are higher than normal. Aiming for roughly 1.2 to 1.5 grams of protein per kilogram of body weight daily is a reasonable target. For a 70 kg (154 lb) person, that’s 84 to 105 grams of protein per day, spread across meals. Good sources include poultry, fish, eggs, dairy, legumes, and tofu. Nutritional guidelines for patients on prolonged glucocorticoid therapy specifically highlight adequate protein intake as a priority for preserving muscle mass and supporting bone health.
What Happens After You Stop
Most prednisone-related weight gain is easier to lose after you taper off the drug than it was to prevent while taking it. The fluid retention typically resolves within days to weeks as your kidneys return to normal sodium handling. The metabolic changes, including insulin resistance and altered fat distribution, take longer. Full recovery can take anywhere from a week to several months, depending on how long you were on the drug and at what dose.
The fat redistribution to your face, neck, and abdomen gradually reverses as your cortisol levels normalize. Moon face is often one of the last visible changes to resolve, but it does resolve for most people. Muscle mass that was lost during treatment can be rebuilt with consistent resistance training and adequate protein, though this takes time and effort.
A Note on Metformin
A phase 2 clinical trial at Barts Health NHS Trust found that metformin, a widely available diabetes drug, improved metabolic outcomes in non-diabetic patients on high-dose glucocorticoids. Patients treated with metformin showed beneficial results across cardiovascular, metabolic, and bone markers over a 12-week trial. The researchers found that metformin appears to work through the same metabolic pathway that steroids disrupt, essentially pushing back against prednisone’s effects. If you’re on a high dose for an extended period and struggling with weight gain or blood sugar changes, this is worth discussing with whoever prescribes your prednisone.