Nutrition in Paediatrics

Nutrition encompasses all processes related to the intake, assimilation, and utilization of the proper nutrients necessary for maintaining health, well-being, and productivity. While closely related, the terms 'nutrition' and 'food' are not interchangeable. Nutrition represents the series of events, whereas food refers to the products consumed by the body.

What is Nutrition?

"Nutrition is the science that studies foods and how food nourishes our bodies and influences our health."

What is Malnutrition?

"Malnutrition occurs when nutrient and energy intake does not meet or exceeds an individual’s requirements to maintain growth, immunity, and organ function. It is a general term and covers both undernutrition and overnutrition."

Importance of Food/Nutrition

• Food contains essential nutrients necessary for the following:
• Developing, growing, maintaining, replacing, and repairing cells and tissues.
• Resisting and fighting infections, as well as recovering from illnesses.
• Producing energy, warmth, movement, and the ability to perform work.

Nutrition Basics

• Nutrients: Substances in food that the body requires to function properly.
• Nutrition: The sum of all processes involved in food intake, assimilation, and its utilization within the body.
• Diet: The amount and type of food and drink an individual consumes.
• Balanced Diet: The daily provision of food that includes all nutrients in the correct amounts and combinations necessary to meet the body's functional needs.
• Metabolism: The body's physical and chemical processes that break down food and convert it into useful forms of energy.
• Nutritional Status: The health status of the body in relation to a nutrient or group of nutrients, reflecting the body's response to nutrients and resulting outcomes.
• Good Nutrition: Involves consuming a variety of safe and appropriate foods in the correct quantities to meet the body's requirements for health and well-being.
• Undernutrition: A condition resulting from inadequate nutrient intake.
• Overnutrition: A condition resulting from an excess intake of nutrients.

Undernutrition is the result of insufficient intake of energy, macronutrients, and/or micronutrients, poor nutrient absorption, or nutrient loss due to illness or increased energy requirements.

Overnutrition is characterized by excessive energy consumption or an overabundance of a specific nutrient. It can lead to impaired body functions, chronic diseases, overweight, and obesity.

Forms of Undernutrition

Undernutrition can manifest in various forms:

• Acute Malnutrition: Often results from short-term insufficient food intake combined with frequent illness. It typically presents as a rapid loss of weight due to the depletion of fat and muscle. There are two important clinical forms:
• Moderate Acute Malnutrition (MAM): A condition characterized by moderate weight loss due to inadequate food intake.
• Severe Acute Malnutrition (SAM): A severe form of malnutrition, often resulting in significant weight loss, muscle wasting, and other severe health consequences.
• Chronic malnutrition: results from inadequate nutrition over an extended period, potentially leading to the failure of linear growth or stunting. Maternal undernutrition can also manifest as stunting in children.

Micronutrient deficiencies refer to the critical lack of certain essential vitamins and minerals, such as vitamin A, vitamin D, zinc, and iodine, which are vital for human survival, health, and well-being. These nutrients are required in very small quantities, hence the term "micronutrients."

Overnutrition

Overnutrition occurs when there is an excessive intake of energy or a surplus intake of specific nutrients. It can lead to impaired body functions, the development of chronic diseases, and result in conditions like overweight and obesity.

The Double Burden of Malnutrition

The Double Burden of Malnutrition is defined as the coexistence of both undernutrition and overnutrition within the same population across the life course. "Across the life course" refers to the phenomenon where undernutrition early in life contributes to an increased propensity for overnutrition in adulthood.

Classification of Nutrients

Nutrients can be classified into two main categories:

• Macronutrients: These are nutrients required by the body in relatively large quantities, often measured in grams per day. They include carbohydrates (CHO), proteins, and fats.
• Micronutrients: These are nutrients needed by the body in very small quantities, usually less than 1 gram per day. Micronutrients comprise 13 vitamins and 17 essential minerals.

ESSENTIAL NUTRIENT GROUP

The key nutrient groups essential for human health include:

• Carbohydrates
• Proteins
• Fats
• Vitamins
• Minerals
• Water

Energy: Fuel for Work

Energy source:

• Chemical energy in carbohydrates, fat, protein

Catabolism:

• Reactions that break down compounds into small units

Anabolism:

• Reactions that build complex molecules from smaller ones

Food energy to cellular energy:

• Stage 1: Digestion, absorption, transport
• Stage 2: Breakdown of molecules
• Stage 3: Transfer of energy to a form cells can use

Approximate average energy expenditure in children:

• Basal metabolism – 50%
• Physical activity – 25%
• Growth – 12%
• Fecal loss – 8%
• Thermal effect of food – 5%

Energy:

• Calories in human milk:
• Protein: 9-15%
• Carbohydrate: 45-55%
• Fat: 35-45%
• Calories in older children's food:
• Protein: 10-15%
• Carbohydrate: 55-60%
• Fat: 30%
• Kcal each gram of ingested food contains:
• Carbohydrate: 4 kcal/gram
• Protein: 4 kcal/gram
• Fat: Saturated (SCH) - 5.3 kcal/gram, Monounsaturated (MCH) - 8.3 kcal/gram, Polyunsaturated (LCH) - 9 kcal/gram

Carbohydrates are the macronutrients needed in the highest amount. They are the primary source of energy for the body and are converted to glucose to be used as fuel.

Carbohydrates

Carb Sources: Carbohydrates can be found in various foods, including vegetables, fruit, rice, maize, grains, potatoes, wheat products, beans, legumes, milk, yogurt, kefir, and other dairy products. Refined carbohydrate sources like fizzy drinks, cookies, and candies are examples of refined carbohydrates.

Quick Facts about Carbs:

• 45-65% of daily calories should come from carbohydrates (USDA).
• The type of carbohydrate is more important than the quantity. Foods high in fiber, such as fruits, vegetables, beans, legumes, and whole grains, have many health benefits, while more refined carbohydrate-containing foods, such as those with refined sugar or grains, have fewer benefits.
• Carbohydrates provide 4 calories per gram.

Carbohydrate:

• They are often referred to as energy-giving foods.
• Make up a large percentage of energy in the diet, especially in developing countries.
• Can be classified into:
• Digestible: Also known as simple carbohydrates, these are quickly digested and absorbed but lack fiber. They are often referred to as empty calories. They include monosaccharides (glucose and fructose), disaccharides (lactose, sucrose, maltose), and plant starch.
• Indigestible: Also known as complex carbohydrates, these typically provide more fiber along with vitamins and minerals. They are usually digested in the colon by specific colonic flora and act as prebiotics in the body. Examples include dietary fibers such as cellulose, lignin, pectin, and oligosaccharides found in breast milk.

Proteins provide the body with essential amino acids that serve various functions, including growth and development, tissue repair, production of enzymes and hormones.

Protein Sources

• Meats, poultry, fish, cheese, milk, nuts, legumes, and, to a lesser extent, in starchy foods and vegetables.
• Proteins are composed of amino acids and are present throughout the body, forming part of every cell, tissue, and organ (e.g., hair, skin, blood, nails, bones).

Quick Facts about Protein:

• The Recommended Dietary Allowance (RDA) for protein is 0.8g/kg of body weight per day. At least 10-35% of daily calories should come from proteins.
• Proteins provide 4 calories per gram.

Proteins:

• Proteins are comprised of amino acids, which can be classified as essential (indispensable) or non-essential (dispensable) amino acids.
• Essential amino acids include histidine, methionine, isoleucine, leucine, lysine, phenylalanine, threonine, tryptophan, and valine.
• Non-essential amino acids include alanine, aspartate, asparagine, glutamic acid, and serine.
• Proteins, also known as the bodybuilding food, form structural components of cells and make up the bulk of tissues and organs.
• Their major functions include growth, development, maintenance, repair of tissues, and replacement of worn-out or damaged tissues. Proteins are also involved in the production of metabolic and digestive enzymes, as well as certain hormones in the body.
• Protein sources can be of high quality, providing all nine essential amino acids, or low quality, lacking some essential amino acids.
• Animal sources of protein are high-quality protein, including milk, eggs, cheeses, yogurt, and fish.
• Plant sources of protein are considered low-quality protein as they are often deficient in some essential amino acids. Examples include legumes, nuts, and vegetables.

Fats are often 'feared' nutrients due to their association with weight gain and their presence in processed foods. However, they are essential for the healthy functioning of the body and provide the most concentrated source of energy, offering 9 calories per gram.

Fat Sources

• Monounsaturated and Polyunsaturated Fats: Sources include olive oil, avocados, nuts, seeds, fish, vegetable oils (e.g., sunflower oil, canola oil).
• Saturated and Trans Fats: These fats are found in cream, lard, fried foods, snacks, and baked goods.

Quick Facts about Fats:

• They are needed for the absorption of fat-soluble vitamins (A, D, E, & K).
• Omega-3 fatty acids are beneficial for heart health.
• 20-35% of daily calories should come from fats, but the type of fat consumed is more important than the quantity. Consuming too many foods high in saturated fats, including trans fats, can increase the risk of some chronic diseases.

LIPIDS/FATS

• Lipids are found in fats and oils and are a concentrated source of high-energy that is slowly absorbed by the body.
• They provide essential fatty acids (FAs) that the body cannot produce itself.
• The essential FAs important for children are Linoleic acid (n-6) and α-linoleic acid.
• Lipids in food can be visible, as found in butter and vegetable oil, or invisible, as found in nuts, cheese, egg yolk, and milk.
• Functions of lipids include composing membrane lipids, providing structural components for the brain and retina, affecting gene expression, as well as serving as the body's primary store for energy.

What are Micronutrients?

Micronutrients are the 'vitamins and minerals that are essential for human survival, health, and well-being.' These nutrients are required in very small quantities, hence they are called Micronutrients.

Examples: Iron, iodine, zinc, folate, and vitamins

What is Hidden Hunger?

Hidden hunger is the phrase used to describe the critical lack or deficiency of these micronutrients. This is the 'hunger' that is usually neither obvious nor felt but has threatening consequences for the population's physical and mental health, especially for pregnant mothers and growing children.

Vitamins & Minerals

Vitamins

• Group of organic compounds that play important functions in the body. Some can be stored in the body while others cannot and should be eaten frequently.
• Vitamins play key roles in the body, such as building cells, protecting cells from damage, and helping them heal.
• Examples: Vitamin A, vitamin D, vitamin C

Minerals

• Solid, inorganic group of compounds that are essential building blocks of different types of cells.
• Examples: Iron, zinc, calcium, iodine

VITAMINS

• Vitamins are organic compounds that perform specific metabolic functions in the body.
• The body does not synthesize most vitamins, so they must be provided by food.
• Unlike carbohydrates, protein, and fats, vitamins do not produce energy. However, they are necessary for the metabolic processes that produce energy.
• There are 13 Vitamins which can be classified into two categories based on the substance in which they dissolve:
• Fat-soluble vitamins: These vitamins can be stored in the body when not used. They include vitamin A (maintenance of eyes), D (bones and muscles), E (cellular integrity), and K (blood hemostatic).
• Water-soluble vitamins: These vitamins must be supplied daily in food as the body has limited ability to store them. They include vitamins B1 (Thiamine), B2 (Riboflavin), B3 (Niacin), B6 (Pyridoxine), B12 (Cobalamin), Vitamin C, Pantothenic acid, Folic acid, and Biotin.

MINERALS

• Minerals are inorganic compounds that are not produced by the body but are required.
• They are referred to as trace elements because they are needed in very small quantities.
• Minerals influence many of the body's biochemical reactions and are used to form cells and tissues.
• Common minerals include:
• Iron: Essential for blood formation.
• Zinc: Important for the immune system.
• Calcium: Important for bone health.
• Iodine: Vital for the brain.
• Others include magnesium, copper, phosphorus, selenium, nickel, and fluoride.

Water is the body's principal fluid, making up about 60% of the body weight. It is important for regulating temperature and maintaining body functions.

Sources

• Environment
• Foods and beverages, including fruits, vegetables, milk, and juice.

Quick Facts:

• Recommendations for fluid intake per day vary based on age, gender, climate, and activity level.
• During pregnancy, drinking fluids is even more important as the body is going through many changes.

WATER

• Water is an essential nutrient because it is necessary for body functions, including digestion and other metabolic processes.
• It is a primary component of the body, representing over 60% of the total body weight.
• An average absolute requirement of water for children is 75 – 100ml/kg/24hrs.

1. Grains (including roots and tubers)
2. Vegetables & Fruits
3. Meats & Alternatives (including legumes, nuts, seeds, poultry, fish, and eggs)
4. Milk & Alternatives
5. Fats & Oils

GRAIN (INCLUDING ROOTS AND TUBERS)

• A source of carbohydrates
• Choosing high-quality grains, which are high in fiber, is better as they are absorbed slowly.
• Examples: Porridge, breads, chapati, cereals – composed of flours (maize, rice, wheat, millet, sorghum)

Servings Per Day:

• Adults (19-51+ years): 7-10
• Adolescents (9-18 years): 6-7
• Children (4-8 years): 4
• Children (2-3 years): 3

VEGETABLES AND FRUITS

• Critical component of a healthy diet
• Good source of fiber

Servings Per Day:

• Adults (19-51+ years): 7-10
• Adolescents (9-18 years): 6-8
• Children (4-8 years): 5
• Children (2-3 years): 4

MEATS AND ALTERNATIVES

• Including legumes, nuts, seeds, fish, poultry & eggs
• Excellent sources of protein

Servings Per Day:

• Adults (19-51+ years): 2-3
• Adolescents (9-18 years): 2-3
• Children (4-8 years): 1
• Children (2-3 years): 1

MILK AND ALTERNATIVES

• Good source of essential vitamins and minerals, especially calcium and vitamin D
• Examples: Milk, yogurt, cheese

Servings Per Day:

• Adults (19-51+ years): 2-3
• Adolescents (9-18 years): 3-4
• Children (4-8 years): 2
• Children (2-3 years): 2

FATS AND OILS

• Important to choose healthy fats (unsaturated fats) in the diet, e.g., avocados, nuts, olive oil
• Limit saturated fats and trans-fats, e.g., lard, butter, shortening
• 2 to 3 tablespoons (30-45 mL) of unsaturated fat each day is important for the absorption of some vitamins and minerals
• Limit those high in saturated and trans-fats to 1 tsp per day

A 'healthy eating plate' is a concept that can help guide better food choices and servings:

• Half of the plate should consist of vegetables and fruits.
• A quarter of the plate should be grains.
• Another quarter should be dedicated to protein.
• Don't forget to incorporate healthy fats and oils, and remember to drink water.

Fortification and Enrichment

Let's understand the terms:

• Fortification: The practice of deliberately increasing the content of essential micronutrients like vitamins and minerals (including trace elements) in a food. This is done to improve the nutritional quality of the food supply and provide a public health benefit with minimal risk to health.
• Enrichment: Enrichment is synonymous with fortification. It refers to the addition of micronutrients to a food, regardless of whether those nutrients were originally present in the food before processing or not.