The best way to gain weight is to eat slightly more calories than your body burns each day while strength training to ensure those extra calories build muscle rather than just fat. Experts recommend eating 10–20% above your maintenance calories, which produces a steady gain of about 0.25–0.5% of your body weight per week. For a 150-pound person, that works out to roughly 0.4 to 0.75 pounds per week, a pace that favors lean tissue over excess fat storage.
How Many Extra Calories You Actually Need
The number that matters most is your calorie surplus: the gap between what you eat and what your body uses. A 10–20% increase over your daily maintenance needs is the sweet spot. If you normally burn around 2,200 calories a day, that means eating 2,420 to 2,640 calories instead. It sounds modest, and that’s the point. A smaller, consistent surplus directs more energy toward muscle growth and less toward fat gain.
If you’re gaining less than 0.25% of your body weight per week, bump your intake up slightly. If you’re gaining faster than 0.5% per week, you’re likely adding more fat than necessary. Weigh yourself at the same time each morning, average the week’s readings, and adjust from there. This kind of tracking removes the guesswork and keeps your progress visible.
What to Eat for Healthy Weight Gain
Gaining weight doesn’t mean eating anything in sight. A diet heavy in processed foods and refined sugars promotes visceral fat, the deep abdominal fat linked to diabetes, high cholesterol, and cardiovascular disease. Diets high in fatty foods and excess sugar specifically encourage visceral fat formation, which behaves differently from the fat under your skin. It actively influences your hormones and metabolism, raising your risk of metabolic disease over time.
Instead, focus on calorie-dense whole foods that pack nutrition into every bite:
- Nuts and nut butters (almonds, walnuts, cashews, natural peanut butter): spread on toast, stir into oatmeal, or add to trail mix
- Fatty fish like salmon, tuna, and sardines, which provide both calories and heart-healthy fats
- Avocados and olives: easy to add to sandwiches, eggs, salads, and Mexican dishes
- Olive oil, canola oil, and peanut oil: drizzle over vegetables, pasta, or use as a bread dip
- Seeds and grains like sunflower seeds, chia seeds, ground flaxseed, and wheat germ
- Dried fruit such as dates, prunes, raisins, and apricots, which are surprisingly calorie-dense
- Whole milk dairy: yogurt, cheese, and butter added to potatoes, soups, and sauces
Most of these are unsaturated fats, which protect against heart disease while helping you hit your calorie targets. The goal is to gain weight in a way your body can sustain and that doesn’t create new health problems.
How Much Protein You Need
Protein is the raw material your muscles need to grow. The American College of Sports Medicine recommends 1.2 to 1.7 grams of protein per kilogram of body weight per day for people who exercise. If you weigh 70 kilograms (about 154 pounds), that’s roughly 84 to 119 grams of protein daily. People trying to significantly increase muscle mass should aim for the higher end of that range.
You don’t need to get all your protein from chicken breasts and protein shakes. Fatty fish, eggs, Greek yogurt, cottage cheese, lentils, and tofu all contribute. Spreading protein across three to four meals works better than loading it all into one sitting, since your body can only use so much at once for muscle repair.
Strength Training Drives Muscle Gain
Eating more without exercising will add weight, but mostly as fat. Resistance training signals your body to use those extra calories to build muscle. Two or three sessions per week produces the best results for muscle size and strength. Starting with two workouts per week, spaced a few days apart, and adding a third session as you get stronger is a solid approach.
The key principle is continuous improvement. If you lift the same weight for the same number of repetitions month after month, your muscles have no reason to grow. You need to gradually increase either the weight, the number of sets, or the number of exercises over time. If you don’t notice changes after about eight weeks, you’re not training hard enough. That’s a signal to increase intensity, not to eat more.
Compound movements like squats, deadlifts, bench presses, rows, and overhead presses work multiple muscle groups at once and stimulate the most growth per exercise. These should form the backbone of your routine, with smaller isolation exercises added as needed.
Use Liquid Calories When Eating Feels Hard
One of the biggest obstacles to gaining weight is simply not feeling hungry enough to eat the volume of food required. This is where smoothies and shakes become genuinely useful. Liquid calories are easier to consume quickly and don’t leave you feeling as stuffed as an equivalent solid meal.
A homemade high-calorie shake can easily reach 600 to 800 calories with the right ingredients. Start with whole milk or yogurt as a base, then add peanut butter or another nut butter for calories and protein. Ground dry oats blend smoothly and add both protein and carbohydrates. A banana, some frozen berries, and a drizzle of honey round things out. For extra protein, toss in silken tofu (it won’t change the taste) or a scoop of protein powder. Even pre-cooked and cooled rice or oatmeal can be blended in for additional calories.
Drinking a shake between meals, rather than replacing meals with them, is the simplest way to add 500+ calories to your day without forcing yourself to eat when you’re not hungry.
Small Strategies That Add Up
Beyond the big picture of calories and training, several practical habits make consistent weight gain easier. Eating more frequently helps. Instead of three large meals, try four or five smaller ones. Your appetite is less of a bottleneck when each meal only needs to be 400 to 500 calories instead of 700 to 800.
Add calories to foods you already eat. Stir dry milk powder into soups, mashed potatoes, or hot cereal. Drizzle olive oil over roasted vegetables. Top oatmeal with nuts, seeds, and dried fruit. Spread avocado on sandwiches. None of these changes the character of the meal, but each one adds 100 to 200 calories. Over a full day, those additions compound quickly.
Eating before bed is fine when you’re trying to gain weight. A bowl of yogurt with granola and honey, or toast with peanut butter and banana, gives your body fuel during the overnight fasting period when muscle repair happens.
When Weight Gain Isn’t Working
If you’re eating in a surplus and training consistently but still not gaining weight after several weeks, something else may be going on. An overactive thyroid (hyperthyroidism) speeds up your metabolism and can cause weight loss even when your appetite is normal or increased. Other symptoms include a rapid heart rate, increased sweating, shakiness, anxiety, difficulty sleeping, and changes in bowel habits. If several of these sound familiar, it’s worth getting your thyroid checked with a simple blood test.
Digestive conditions that affect nutrient absorption, chronic stress, and certain medications can also interfere with weight gain. The inability to gain weight despite genuinely eating enough is a medical signal worth investigating, not just a metabolism quirk to push through.