Muscles are, in fact, made in the kitchen. If you spend hours each week at the gym, you want your efforts to show, right? As it turns out, your diet can either make or break your progress, and there are some worst foods for your muscles you’ll want to avoid if you want to see gains.
“Your diet plays a crucial role in supporting muscle growth, as the nutrients you consume provide the building blocks and energy necessary for the development and repair of muscle tissue,” says Jordan Hill, MCD, RD, CSSD, a dietitian with Top Nutrition Coaching. “Certain foods can help promote muscle growth, while others can hinder it.”
For example, high-quality protein, carbs, and fats can all support muscle growth and maintenance. Getting enough protein triggers muscle protein synthesis, the process by which your body repairs and builds new muscle fibers, Hill says. Meanwhile, carbs, especially after a workout, stimulate the release of insulin, a hormone that helps build muscle and transport carbs into muscles to refill glycogen stores. “Carbs combined with protein reduce cortisol, a hormone that causes muscle breakdown, which can help in the pursuit of maintaining current muscle mass,” Hill tells us. And healthy (unsaturated) fats are necessary because of their role in hormone production, including testosterone, which is important for muscle growth.
Below, are the most common foods that contain these offenders, aka the worst foods for your muscles. Quick disclaimer: It’s important to note that these foods can be included in a balanced diet that still supports muscle growth and health. “It’s really when these are consumed in excess and not part of a balanced and varied diet that they can have negative impacts on muscle growth and health,” Hill says.
Now that you know which foods to enjoy just once in a blue moon, check out the 10 Foods That Are Destroying Your Abs.
They may be convenient, but you’ll want to cut your cold-cut habit cold turkey. Cold cuts made from fatty cuts of pork are high in saturated fat and may contribute to muscle impairment. A 2020 study in Clinical Nutrition found that eating too much saturated fat, especially from fatty cold cuts, was linked to lower-extremity functional impairment. Instead of stacking a sandwich with ham and cheese, choose lean meats such as fresh chicken or turkey breast, and pair your sammy with a side salad or roasted veggies.
One slice of frozen pizza will cost you around nine grams of saturated fat, which is nearly half of your daily value—and we bet you’re not just eating a single slice. Eating too much saturated fat can trigger inflammation, which can hinder recovery and growth after the gym. What’s more, many frozen pizzas are high in added sugar (mostly coming from the sauce), which is another nutrient you’ll want to limit to help you build lean muscle.
Your daily coffee shop habit might be to blame for your plateau at the gym. While the caffeine in coffee can help boost your energy to crush a workout, if you’re opting for something like a frappe or caramel latte, you’re getting loads of added sugar. Consuming too much added sugar, as we know, can send your blood sugar levels on a rollercoaster (spiking up, then down), leading to an energy crash probably sooner than you expected. Skip the sugary latte and enjoy a cup of unsweetened coffee with a splash of milk instead.
Pies, cake, cookies, oh my. “Excessive intake of sugary baked goods like cakes and cookies without the intake of a balanced and nutritious diet can negatively impact muscle growth and maintenance,” Hill says. And that’s not all: “High sugar intake is associated with insulin resistance and inflammation, which can interfere with protein metabolism and muscle recovery.”
But you don’t have to trash the entire cookie jar — just make sure to limit how many desserts you enjoy. Reducing the consumption of added sugars to below 25 grams a day can help reduce the negative effect of sugars on your health, according to a 2023 study in the journal BMJ.
Candy, whether it’s sour or sweet, is one of the top sources of added sugars. And eating too much sweet stuff can lead to weight gain and insulin resistance, Hill says. “Insulin resistance impairs the body’s ability to effectively utilize carbohydrates, which can impact energy levels during workouts and nutrient delivery to muscles.” Plus, spikes and crashes in blood sugar levels can affect overall energy and recovery, Hill adds. And that makes it harder to hit the gym as often as you’d like.