Now that you’ve got the initial steps to how to gain weight in mind, what you eat also plays a significant role. If you seek to gain weight, a protein-rich diet and nutrient-dense foods are key. Including these foods in your diet will help you to gain weight the healthy way and aid in building muscle mass with exercise. It is important that you primarily consume healthier foods instead of junk foods when trying to gain weight. Junk foods contain ingredients that are not used for your benefit and can lead to possible adverse health effects. However, don’t be afraid to treat yourself every so often. Just keep in mind to have a healthy and moderate balance.
Here is a list of healthy foods you can include in your diet that will give you a wholesome amount of vitamins and nutrients, and also contribute to weight gain:
Whole wheat / whole grains
Whole wheat and whole grain foods contain multiple nutrients including vitamin B, calcium, fiber, and more. Sources of whole wheat and whole grains include bread, cereal, and pastas. These foods additionally contain a number of calories that can be beneficial when trying to gain weight.
Brown rice
Brown rice is also a whole grain, and carries many healthful perks. Rice in general is a very nutrient-dense food and is packed with calories in a small serving size. Brown rice however, has more of its natural fibers as opposed to white rice, as it hasn’t been as refined.
Potatoes
Potatoes are a healthy source of carbohydrates, densely packed with vitamins and minerals. They are best served baked, grilled, or roasted – not fried. Potatoes can provide around 160 – 230 calories per one potato, making them a satisfying choice for a main meal.
Yogurt
Yogurt is a dairy product that often times contains a blend of added fruits. It can be a favorable snack when trying to gain weight, as yogurt consists of healthy fats and additional calories all in a small size, still leaving room for other meals. Mix in some chia seeds for extra nutrients and reap the benefits.
Beans
Beans are a healthy and major source of protein, iron, and carbohydrates that can be consumed with any meal. Black beans, kidney beans, and pinto beans, all have a decent number of calories per serving size, which make good for gaining weight. Beans are also a good choice of foods to gain weight for vegetarians who seek to get protein elsewhere instead of meat.
Seafood
Seafood can be an advantageous source of nutrition, as it is enriched with vitamins, minerals, and proteins needed for growth and development among other functions. Tuna, salmon, and shellfish are your best bet when it comes to weight gain. These sea foods hold around 200 calories or more per serving, and don’t include as many unhealthy saturated fats.
Fruits & vegetables
Don’t forget your fruits and vegetables. These foods are a necessity in our diet. They help to perform healthy body functions, promote a strong immune system, and lower your risk for certain diseases. Whether you eat them as a snack or add them alongside your main meals, fruits & vegetables are a gainful source of nutrient-rich calories.
Dried fruits
Dried fruits typically have more of their natural healthful nutrients compared to grocery fruits, because they are essentially being preserved. Containing around hundreds of calories per serving, these snacks are a great choice of foods to gain weight.
Olive oil
Olive oil, along with other vegetable oils (e.g. avocado oil, canola oil) can be helpful when trying to gain weight, specifically when used for cooking. Per teaspoon, these oils can carry around 100+ calories, making for a healthy additive that blend in naturally with your meals.
Lean red & white meats
Meats are a beneficial choice of high-protein foods to gain weight and when consumed, help to promote healthy muscle growth. Lean cut meats are meats that have more of their fat content removed. When and if you do consume meat, try to go for the lean cut and unprocessed choices.
Granola
Granola and trail mixes can include a blend of nuts, seeds, and dried fruits – all high calorie and nutrient-dense bite sized edibles. Include these in your diet for breakfast or as a healthy snack for a boost of energy.
Nuts & seeds 
Cashews, peanuts, chia seeds, and flax seeds are just a few examples of healthy nuts and seeds you can introduce into your diet. These small eatables hold a surplus of calories and vitamins and minerals.
You can add seeds to your smoothies and yogurt, or blend in nuts with trail mixes and consume them as a healthy snack. However you consume them, eating these foods to gain weight will be for the betterment of your health in the long-run.