A lot of people start the keto diet because they want to lose weight or improve their health. 

But if you’re trying to gain a few pounds to reach a healthy weight, a high-fat, low-carb diet like keto may work well for you, too. 

One of the main challenges with weight gain is eating a large number of calories in a day. Some people still think that the only way to do that is by eating tons of carbs — brown rice, bagels, granola, and other carb-dense foods. 

However, carbs only contain 4 calories per gram, which means you have to eat a lot of them to gain weight. Fat, on the other hand, has 9 calories per gram, making it the most calorie-dense macronutrient. 

Eating high-fat, low-carb food is a great way to reach your target amount of calories without having to constantly snack throughout the day. 

A healthy keto diet also includes many high-protein foods, which helps you put on muscle, not just fat. If you’re looking for a healthy high-calorie diet, keto is a great option. It also has a variety of health benefits, like lower inflammation[*] and healthier aging[*]. 

Here’s a look at 9 of the best calorie-dense, healthy foods to eat on a keto diet, along with their nutrition facts. 

The 9 Best High-Calorie Keto Foods 

1. Ribeye Steak

Ribeye steak is the fattiest cut of beef on the cow, which also makes it the most calorie-dense steak (and one of the most flavorful steaks). 

Steaks come in different grades based on their fat content. Prime steaks are the fattiest, while choice steaks are leaner and have fewer calories. 

Most ribeye steaks are about 16 ounces and contain roughly 1600 calories. Ribeyes are also an excellent source of protein, making them ideal if you’re trying to gain muscle. 

For extra calories, try topping your steak with grass-fed butter or olive oil, garlic, and fresh herbs.  

Serving size: 4 oz

Calories per serving: 400

2. 80% Lean Beef

Eating prime steak every meal can get expensive. A more affordable calorie-dense option is 80% lean ground beef. 

At 20% fat, this ground beef is particularly juicy and flavorful, which makes it perfect for burgers or keto meatballs. It also contains more calories than its leaner counterparts. 

For extra calories, top your burger with bacon, cheese, mayonnaise, or other high-fat, keto-friendly options. 

Serving size: 4 oz

Calories per serving: 300

3. Fatty Fish

Wild fatty fish are an excellent source of omega-3s, healthy fats that lower inflammation[*] and improve brain function[*]. 

Fatty fish are also calorie-dense and a good source of protein. To choose the right fish, remember the acronym SMASH, which stands for:

• Salmon
• Mackerel
• Anchovy
• Sardine
• Herring

These five fish are all high in omega-3s and low in mercury. 

Avoid fish that are high on the food chain, like shark, swordfish, or tuna (except skipjack tuna, which is fine). Larger predatory fish are high in mercury, a toxic heavy metal. The FDA recommends that you only eat high-mercury fish once every couple weeks, if at all[*]. 

Serving size: 4 oz

Calories per serving: 200

4. Nut Butters

Nut butters are high in monounsaturated fat, a healthy fat that may support heart health if you eat it on a regular basis[*].

Nut butters are also particularly nutrient-dense. They’re rich in vitamin E, magnesium, selenium, and a variety of other vitamins and minerals. 

 Almond butter, peanut butter, pecan butter, and macadamia nut butter are all good choices. 

You can also try Perfect Keto nut butters — extra high-fat nut butters in flavors like snickerdoodle, chocolate hazelnut, and almond butter and jelly. 

Serving size: 2 tbsp

Calories per serving: 200-300

5. Whole Milk Greek Yogurt

​Full-fat Greek yogurt is packed with both fat and protein, as well as probiotics that improve digestion and support healthy gut bacteria[*]. 

Be sure to check the nutrition label on Greek yogurt before you buy it — some brands have added sugar that makes them too high in carbs for a keto diet. 

Serving size: 1 cup

Calories per serving: 200

6. Full-Fat Cheese

Cheese is high in both fat and protein, making it perfect for a keto diet. It’s pairs well with a variety of foods, and its high calorie density makes it an easy way to increase the calorie count of your meals. 

Grate parmesan on salads (and use a keto salad dressing), serve a keto cheese dip with fresh vegetables, or make keto cheeseburger casserole for dinner. 

Serving size: 1 oz 

Calories per serving: 110

7. Avocado

Avocados are nutritional powerhouses. These high-fat fruits are packed with fiber, antioxidants, heart-healthy monounsaturated fats, and a wide variety of vitamins and minerals. 

Try making zesty keto guacamole and eating it with fresh low-carb veggies (or put it on top of a burger). 

Serving size: 1 avocado

Calories per serving: ~300

8. Dark Chocolate

Dark chocolate is an exceptional source of polyphenols, a special class of antioxidants that enhance brain function[*] and protect your cells from stress[*]. 

To keep carbs low, choose 70% dark chocolate or higher, or find a milk chocolate that’s sweetened with stevia, monk fruit, or another natural keto sweetener. 

Serving size: 1 oz

Calories per serving: 170

9. Butter Coffee

Butter coffee is one of the best ways to get extra calories at breakfast. The basic butter coffee recipe includes:

• 2 cups freshly brewed coffee
• 2 tbsp grass-fed butter
• 1 tbsp coconut oil or MCT oil 

All you have to do is blend everything together until creamy. You can also add extras like cinnamon, vanilla, cocoa powder, or collagen protein. 

Serving size: 16 oz

Calories per serving: 300

Can High-Calorie Foods Be Healthy?

When you’re trying to gain weight, it’s especially important to pay attention to food quality. You may be able to gain weight by eating fast food and sugar-laden desserts, but you’ll also damage your body and set yourself up for possible health problems in the future. 

To gain weight in a healthy way, you want to make sure you choose the right high-calorie foods. 

Avoid the following:

• Desserts and baked goods (ice cream, candy, cookies, muffins, cakes)
• Canola oil, soybean oil, corn oil, and other vegetable oils (they’re high in inflammatory omega-6 fats[*]) 
• High-sugar foods (including natural sources, like dried fruits and honey)
• Refined carbs (white bread, bagels, pasta)
• Fried foods (fried chicken, french fries, potato chips)
• Fast food

Instead, eat plenty of nutrient-dense, calorie-dense whole foods, like the ones listed in this article. For more guidance, consider talking to a registered dietitian who can help you meet your goals. 

You may also want to start lifting weights to build muscle, which will help you gain weight faster. 

The Takeaway

If you’re trying to gain weight, following a keto diet may help. 

Keto includes a wide variety of healthy high-calorie foods that make it easier to hit your calorie goals without eating constantly throughout the day. You can start keto today — as long as you follow a couple basic rules, it’s a simple way to eat. 

However you decide to gain weight, be sure to avoid sugary desserts, fried snacks, fast food, refined carbs, and other unhealthy food choices. With the right diet plan, you can gain weight in a healthy, sustainable way.