Introduction

Weight gain improves physical and mental well-being and various body functions. Achieving and maintaining a healthy weight is essential for general health as it can provide energy for daily activities, promote proper organ function, and aid in the development and maintenance of muscle and bone mass. Gaining weight in a balanced and controlled manner is crucial to avoid potential health risks associated with rapid or unhealthy weight gain, especially for individuals recovering from an illness. 

Though there are benefits in gaining weight, there are misconceptions that any form of weight gain is beneficial can lead to habits that compromise overall health. Ignoring the nutritional quality in the weight gain process can be detrimental and lead to more issues than benefits. 

As weight gains, the speed needs monitoring. A rapid weight gain may have potential health risks and is not entirely an indicator of success. Furthermore, gaining weight does not revolve around nutrition. Regular physical activity, particularly strength training, is crucial for building muscle mass.

Gaining weight involves going through and making thoughtful dietary choices and understanding caloric requirements. There can be several reasons to gain weight, to build muscle or recover from a period of weight loss and to incorporate the right amount of proteins, healthy fats, and carbohydrates is important. 

Caloric surplus and macronutrients

Every person has individual calorie requirements to maintain their body weight, which is termed as the total daily energy expenditure (TDEE). Weight, height, gender, age and activity levels, help to estimate calories needed to maintain the weight. Going below the TDEE would result in a weight loss, and going above the TDEE would cause a weight gain. 

Food and beverages are the main methods of calorie supplementation in the body. To gain weight healthily and beneficially, understanding foods and their individual components is crucial. 

The three main macronutrients in foods are proteins, fats, and carbohydrates. Having a diet that is a mixture of all three components in balanced quantities would allow for a safe and healthy weight gain, as each macronutrient has its own functions and benefits. 

Proteins play a pivotal role in maintaining and promoting various functions like building and repairing tissues, supporting the immune system, and facilitating the production of enzymes and hormones. A protein diet can cause muscle development and provide sustained energy when carbohydrate stores deplete. Ensuring adequate intake of proteins during a weight-gaining process can allow a higher portion of muscle mass to be built, with research showing that 1.6 grams of protein per kilogram is the required formula.¹

Carbohydrates are one of the most fundamental sources of energy for the body. The main types of carbohydrates are sugars, starches, and fibres, which then are broken down into glucose, and fuel different body functions. Carbohydrates stored as glycogen in the muscles and the liver, provide readily available energy during physical activities.

Furthermore, complex carbohydrates promote a healthy digestive system, sustained and prolonged energy, and better overall well-being. Carbohydrates are available in fruits, vegetables, grains, with the U.S. Food and Drug Administration (FDA) recommending 275 grams of total carbohydrates daily in a 2000-calorie diet

There are different types of fats; monounsaturated, polyunsaturated, saturated and trans fats. Healthy fats are considered as monounsaturated and polyunsaturated while the unhealthy ones are saturated and trans fats. Healthy fats play a vital role in nutrient absorption, particularly fat-soluble vitamins like A, D, E, and K. Additionally, healthy fats contribute to the maintenance of cell structure, hormone production, and brain function. According to the World Health Organization (WHO), an adult should consume no more than 30% of their calories through fats

Nutrient-dense foods

Many foods can provide a portion of each of the macronutrients, but finding nutrient-dense foods would allow for safe, quick and healthy weight gains. 

Lean proteins

Proteins can be found in large quantities from meats, along with high- fat content. Going for lean protein will allow a higher concentration of protein consumption in comparison to fats and carbohydrates. 

Lean sources of protein include:

• White fleshed fish
• Greek yoghourt
• Chicken breast
• Beans and lentils

Complex carbohydrates

The main types of carbohydrates are simple and complex. Simple carbohydrates are easier to break down by the body and cause a rapid rise and fall in the blood sugars. Complex carbohydrates provide a sustained and lengthened energy source, and are the healthier options.

Complex carbohydrate sources include:

• Legumes
• Sweet potato
• Oats
• Brown rice

Healthy fats

Monounsaturated and polyunsaturated fats on consumption strengthen the cardiovascular health, improve cholesterol levels, and provide other health benefits. 

Sources of “healthy fats” include:

• Avocado
• Tuna
• Chia seeds
• Almonds

High-calorie, nutrient-rich foods

Surplus calories are required to gain weight quickly. Though junk food may be calorie-dense, they are high in unhealthy/bad fats, simple carbohydrates and their prolonged consumption can lead to a multitude of health problems along with weight gain. 

Some foods are high in calories and rich in nutrients that can allow for adequate sustenance for the body. 

Dried fruits and nuts

Dried fruits provide concentrated sources of vitamins, minerals, and natural sugars, and offer energy-dense snacks. Nuts are high in value for healthy fats and protein, while providing sustained energy and supporting muscle development. A variety of dried fruits and nuts t can enhance overall calorie intake. 

Along with providing a high source of calories, research has shown that dried fruits can improve glucose metabolism and strengthen cardiovascular health, while nuts can positively affect blood pressure.^2,3

The calories in 100 grams of various dried fruits and nuts:

• Cashews- 553
• Almonds- 579
• Dried plums- 240
• Dried peach- 239

Nut butter and seed butter

Nut butters and seed butters, such as almond butter, peanut butter, and sunflower seed butter are rich in healthy fats and proteins provide energy. Choosing nut and seed butter over animal sources in meals or snacks can allow a convenient and quick way to increase overall calorie intake. 

The calories in 100 grams of various nut and seed butters:

• Almond butter- 614
• Peanut butter- 588
• Sunflower seed butter- 617

Full-fat dairy and yoghurt

Full-fat dairy products, which includes whole milk and yoghurt, can also be beneficial to gain weight healthily. Dairy products have high quantities of vitamin D and calcium, while also being high in calories. Full-fat yoghurt also contains probiotics that support and promote gut health. 

A 2020 study showed that full-fat yoghurt and other fermented dairy products such as cheese can be protective against cardiovascular diseases and type 2 diabetes.⁴

The calories in 100 grams of various full-fat dairy products:

• Full-fat yoghurt- 61
• Full-fat milk- 63
• Cheddar cheese- 402
• Feta cheese- 264

Snack options

Snacking between the regular meals can be an effective and delicious way to boost calorie intake. Using nutrient-dense snacks that provide a mix of carbohydrates, proteins, and healthy fats high in calories can help a quick weight increase. 

Trail mix

Trail mix is relatively easy to make and is a calorie-dense and nutritious snack. It is prepared by combining different kinds of nuts, seeds, dried fruits, and dark chocolate. 100 grams of trail mix can contain more than 450 calories.

Greek yoghurt with granola and fruits

Greek yoghurt is a dairy product that is high in protein and healthy fats. It can be mixed with granola, nuts, and fruits to make a snack that is rich in essential macronutrients. A serving of greek yoghurt with granola and fruits can have more than 250 calories.

Nut/seed butter snacks

Using nut or seed butter spread on whole-grain breads and adding fruit slices such as bananas can make a calorie dense snack. A slice of bread with peanut butter and banana can contain more than 200 calories. 

Meal timing

Aiming for 3 regular spaced meals allows the distribution of calories. Healthy snacks are given between the meals to add to the surplus. Meals at regular intervals optimize energy levels, nutrient absorption, and protein synthesis.

Pay attention to how the body responds to different meal timings and adjust accordingly. An ideal rhythm consistent with meal times will help regulate appetite and ensure consistent nutrient intake.

Exercise and muscle-building

Through exercise lean muscle mass will develop as opposed to fat.

Strength training, including weight lifting and resistance training, will stimulate muscle growth. A 2016 study showed that irrespective of strength and frequency, both resulted in an increase in the overall lean mass and strength.⁵ 

Furthermore, exercise improves bone strength and mass.⁶ It benefits all with weak and brittle bones.

Creating a meal plan

A meal plan helps to gain weight quickly and safely. TDEE is estimated. TDEE helps to calculate calories. There are 7,700 calories in 1 kilogram. The calorie surplus can be formulated based on the individual needs. We need to emphasise gradual weight increase.

Three regular meals with two snacks can be the aimed nutrition intake, with each of the meals/snacks being dense in macronutrients and snacks. If there is a higher intake of protein it can allow for more muscle gain. 

A variety of foods allow long-term consistency and goals. Consult a registered dietitian or a health professional for personalised guidance.

Summary

Gaining weight quickly and safely involves incorporating nutrient-dense foods that provide essential calories and promote overall well-being. Focus on incorporating a variety of food groups like lean proteins, healthy fats, and complex carbohydrates to have a healthy and safe weight gain. Consistent meals and snacks, complemented by strength training exercises, create a strong approach. Finally, adjusting the goals, meal plans and exercises allows for long-term consistency and maximising the benefits.