1. Milk

Milk has been used as a weight gainer or muscle builder for decades 
It provides a good balance of proteins, carbs, and fats and is a good source of calcium, as well as other vitamins and minerals 

For those trying to add more muscle, milk is an excellent protein source that provides both casein and whey proteins. Research has even shown it can help you add muscle when combined with weightlifting 

Additionally, studies have found that milk, or whey and casein combined, can lead to greater mass gain than other protein sources 

Try drinking one or two glasses of whole milk (149 calories per cup) as a snack, with a meal, or before and after a workout if you’re training 

Milk smoothies are also a delicious way to add milk to your diet. For an easy morning protein boost, try blending up 1 cup of frozen berries, 1 cup of whole milk, 2 teaspoons of honey, and 1 teaspoon of vanilla (about 275 calories).

2. Nuts and nut butters

Nuts and nut butters are perfect choices if you’re looking to gain weight.

Just one small handful of raw almonds (1/4 cup) contains 170 calories, 6 grams of protein, 4 grams of fiber, and 15 grams of healthy fats

Since nuts are very calorie-dense, just two handfuls per day with a meal or as a snack can quickly add hundreds of calories.

You can add nut butters to a variety of snacks or dishes, such as smoothies, yogurts, and crackers, to turn them into a high calorie snack in no time.

For a quick pick-me-up, try this peanut butter banana smoothie, with only three ingredients (270 calories, using whole milk). If you have a peanut allergy, substitute another nut butter.

However, make sure you pick 100 percent nut butters with no added sugar or extra oils. Or better yet, make your own from this homemade almond butter recipe. It’s easy to make and easy on your wallet, too.

3. Red meats

Red meats are probably one of the best muscle-building foods available.

For example, 6 ounces (170 grams) of steak contains around 5 grams of leucine.

Leucine is the key amino acid your body needs to stimulate muscle protein synthesis and add new muscle tissue/ It also contains 456 calories and nearly 49 grams of protein.

In addition to this, red meats are one of the best natural sources of dietary creatine, which is possibly the world’s best muscle-building supplement .

Consider choosing fattier cuts, which provide more calories than leaner meats, helping you take in extra calories and add weight.

In one study, 100 older women added 6 ounces (170 grams) of red meat to their diets and performed resistance training 6 days a week for 6 weeks.

The women gained lean mass, had an 18 percent increase in strength, and had an increase in the important muscle-building hormone IGF-1

Both lean and fatty meats are a great source of protein, though fatty meat provides more calories, which can help you gain weight. One of the best-known fatty beef dishes is brisket.

Brisket is known for being time-consuming to prepare, but it can be much easier if you own a slow cooker.

Start this brisket recipe in the morning and you’ll have a nutritious dinner waiting for you in the evening — approximately 300 calories per 3-ounce (85 grams) serving.

4. Protein supplements

Taking protein supplements is a common strategy for athletes and bodybuilders who want to gain weight. There are many types available, including whey, soy, egg, and pea protein.

Whey protein supplements and mass gainers (supplements that can help you gain muscle mass) can be very easy and cost-effective strategies to gain weight, especially when combined with strength training
Some people think whey protein is unhealthy or unnatural, but this isn’t the case. Whey protein is made from dairy and has been shown to help improve health markers and reduce the risk of disease

Protein supplements may be even more important if you’re also training since your daily protein requirements increase.

Like meats and other animal products, whey protein contains all the essential amino acids required to stimulate muscle growth

You can use it before or after your workout and at any other point during the day.

The easiest way to add protein powder into your diet is with a protein smoothie, especially for breakfast. That gives you the rest of the day to add in nutritious meals and snacks to make sure you get a balanced nutrient intake.

Generally, a smoothie that you make yourself will be more nutritious than buying one that’s ready-made, which may have added sugar and flavorings.

Try this basic whey shake recipe to start your day off with a high energy breakfast. For even more protein, try adding in peanut butter, almond butter, flaxseeds, or chia seeds.

Unflavored whey protein can be added to dishes such as soups, mashed potatoes, and oatmeal to increase protein content.

5. Healthy cereals

Healthy cereals can be an excellent source of carbs, calories, and nutrients.

While you should avoid processed, high sugar cereals, healthier forms, such as oatmeal cooked with whole milk, can be a great carb source to add to your diet.

You’ll get about 130 calories from a 1 cup serving of cooked oatmeal, plus the calories in any whole milk or toppings you add

Consider topping your hot oats, overnight oats, or full fat Greek yogurt with:

1. Nuts
2. Dried fruit
3. Chia seeds
4. Fresh berries
5. Homemade granola

Grain-based cereals and oats also contain beneficial nutrients such as fiber and healthy antioxidants

When purchasing cereals, focus on these healthy choices:

1. Oats
2. Granola
3. Multigrains
4. Bran
5. Ezekiel brand

Make sure to read the label and avoid cereals with excess added sugar. Choose those with the most fiber when possible.

Granola is a calorie-dense mixture of cereals, dried fruits, and nuts. It’s rich in protein, fiber, and micronutrients. Just one-half cup of granola can supply between 200–300 calories.

You may want to try making your own granola to avoid the added sugars in some store-bought versions.