A Comprehensive Guide to Child Nutrition and Feeding

Food vs. Nutrition


Food is the way we provide our bodies with the necessary nutrients. It is a voluntary and conscious act that directly affects human health. Food habits vary according to geographic and cultural mores, economic status, and personal preferences.


Nutrition encompasses the series of processes by which the body uses, harnesses, and transforms the substances it receives from food to reach their full utilization. It is an involuntary and unconscious act.

Nutrients and Energy

The essential nutrients can be reduced to six categories:


Found in milk, meat, fish, eggs, vegetables, and nuts, proteins are the main components of body tissues (muscles, bones) and cells.


These are the starches and sugars that serve as the body’s primary energy source. To be used by the body, carbohydrates must be decomposed in the stomach and intestines and then move into the bloodstream. Excess carbohydrates are stored as reserve energy in the long term.


Fats provide a more concentrated source of energy than carbohydrates. They also provide essential fatty acids necessary for growth. Fats are found in butter, lard, oils, nuts, vegetables, dairy products, eggs, chocolate, red meat, and white meat.

Vitamins and Minerals

Vitamins and minerals are vital for the proper functioning of the body. They are essential for growth, energy production, vitality, and general well-being. The body can manufacture some vitamins from other substances present in foods. Known vitamins include A, B, C, D, E, and K. Minerals needed in larger quantities include calcium, phosphorus, sodium, potassium, chlorine, sulfur, and magnesium. Other minerals, such as iron, fluorine, or iodine, are necessary but in smaller quantities. Some functions of vitamins and minerals include the formation of muscles, teeth, eyes, skin, and hair, as well as bone formation.

Water and Fiber

Water and fiber are essential components of blood and the cells of our body. It is advisable to drink 2 liters of water per day for females and 3 liters for males. Drinking enough water increases stool bulk, and fiber facilitates the expulsion of waste products.

The body generates energy by oxidizing foods. After being ingested, foods are decomposed into more elementary units that are absorbed by the small intestine and pass into the blood, which transports them to cells. In cells, the combustion of food takes place, and energy is obtained for the body to perform its vital functions.

The energy requirements of a growing body depend on:

  • Basal metabolic rate and caloric expenditure of the body: 75 kcal/kg during the first 18 months of life and 25-30 kcal/kg in adults.
  • Physical activity: Children need more or less energy depending on their activity level. We estimate approximately 20 kcal/kg per day in the first 12 months.
  • Growth: Approximately 2.5 kcal are needed for growth in childhood.
  • Losses from excreta: 10% of food is lost through urine and feces.
  • Work done on the intake and absorption of food: Between 4-8 kcal/kg per day approximately.

Age | Average Body Weight (kg) | Total Kcal (Both Sexes)

0-2 months | 3-4 | 345-460

2-6 months | 6-8 | 630-840

6-9 months | 8-9 | 760-945

9-12 months | 9-10 | 900-1,000

1-2 years | 11-12 | 1,155-1,260

2-3 years | 13-14 | 1,300-1,400

3-5 years | 16-17 | 1,520-1,615

Types of Nutrients

Nutrients are found in food and serve to meet the basic needs of the organism. They can be classified into two types:

Energy Nutrients

  • Carbohydrates (carbs or sugars)
  • Lipids (fats)
  • Proteins

Non-Energy Nutrients

  • Water
  • Mineral salts

The roles of nutrients can be categorized as energy-providing, regulatory, and structural (protein).

Some vitamins (D) and minerals (calcium and phosphorus) are crucial for growth, building muscle and the nervous system, and strengthening bones.

Age | Weight | Needs

3 days | 3.200 kg | 200-300 ml

10 days | 3.200 kg | 400-500 ml

3 months | 5.400 kg | 750-850 ml

6 months | 7.500 kg | 950-1100 ml

9 months | 8.500 kg | 1100-1250 ml

1 year | 9.500 kg | 1250-1350 ml

4 years | 16.200 kg | Need 1620-1782 ml water

Except when it’s too hot or they have diarrhea or vomiting, infants completely cover their fluid needs with breast milk or formula. A glass of water contains 250 ml.

Main Foods and Their Nutrients

Food | Nutrients

Milk, cheese, and dairy products | Proteins and calcium

Meat derivatives, eggs, and fish | Proteins, iron, and vitamins A and B

Legumes, dried tubers, and fruits | Proteins, carbohydrates, minerals, and vitamins

Vegetables | Mineral salts, vitamins A and C

Fruits | Carbohydrates, minerals, and vitamins A and C

Rice, cereals, pasta | Carbohydrates and vitamin B

Oils, margarine, and butter | Fats and fatty acids

Main nutrients of each food

Important Vitamins

Vitamin | Important for | Found in

Folic acid | Protects against anemia, reduces the risk of heart malformations in the fetus | Green leafy vegetables, yeast, kidney, and liver

Biotin | Metabolism and increases appetite | Meat, vegetables, liver, kidneys

Vitamin A | Vision, hair, and growth | Butter, margarine, eggs, liver, green leafy vegetables, apricot

Vitamin C | Against decay, infection, mucosal bleeding, and mental disorders | Citrus fruits, cabbage, leafy greens, potatoes, kiwis, parsley

Vitamin D | Bones and teeth, protects against rickets, tuberculosis, and osteoporosis | Butter, margarine, fish, egg yolk, milk, and mushrooms

Vitamin B6 | Skin, cramps, convulsions, dizziness during travel | Meats, green leafy vegetables, eggs, onions, salmon, lentils, bananas, and peanuts

Vitamin B12 | Formation of the nervous system | Meat, cottage cheese, cheese, eggs, fish, and liver

Vitamin B1 | Physical and mental performance | Pork, lettuce, tomatoes, yeast, liver, milk, potatoes, and whole wheat flour

Vitamin P | Growth and heart metabolism | Citrus fruits and peppers

Vitamin E | Protects the circulatory system, promotes fertility | Nuts, cereals, vegetables, oil, fish

Pantothenic acid | Metabolism in general | Meats, fish, milk, potatoes, and vegetables

Vitamins found in each food and what they do

Excess of vitamins, whether it comes from food or not, is not harmful, but a deficit may cause serious problems. In addition to vitamins, we need minerals and trace elements (minerals in low concentration in the body).

Essential Minerals

Mineral | Necessary for | Found in

Copper | Respiratory system, bones, and blood | Eggs, fish, meat, liver, wholemeal bread, lentils, lemon, and cocoa

Fluoride | Protects against cavities | Water (in some areas) and mineral water

Iodine | Prevents goiter | Iodized salt and fish

Manganese | Metabolism, osteoporosis | Hazelnuts, almonds, beets, white beans, oatmeal, brown rice

Selenium | Muscles | Mushrooms, coconut, tuna, eggs, barley, and wheat bran

Zinc | Growth, hair, skin, and fertility | Milk, cheeses, fish, lentils, beans, peas

Chromium, cobalt, molybdenum, nickel, silicon, vanadium, and tin | Metabolism | Dairy products, cereals, pulses, and vegetables

Calcium | Development and maintenance of bones and teeth | Cheese, sardines, almonds, yogurt, milk

Potassium | Cells | Meats, plants, bananas, and apricots

Iron | Formation of blood | Meats, eggs, beans, lentils, vegetables, and flaked oats

Sodium | Balance of fluids in the body | Salt (do not overuse)

Phosphorus | Development and maintenance of bones and teeth | Bread, cheese, yeast, milk, vegetables, beef, chickpeas, and lentils

Magnesium | Concentration problems, dizziness, headaches, nervousness, cramps | Cheeses, salmon, herring, almonds, nuts, chocolate, vegetables, and mineral water

Role of minerals in the body and where they are found

Stages of Food

Depending on the type of food, children can be divided into 3 stages:

Stage of Lactation (0-6 months)

  • Only milk is fed for the first 4 to 6 months.
  • Complementary foods are introduced alongside milk from 6 to 24 months.

Stage of Children in the 1st and Preschool Years (2-6 years)

  • Children must eat all kinds of food.
  • They should eat whatever they want and gradually transition to eating like adults.

Stage of the Older Child (6-12 years)

  • Children eat according to the dietary habits they have received.

Breast Milk vs. Formula

Mother’s Milk

Mother’s milk meets all the nutritional needs of an infant and is easily digested. It contains antibodies that protect against disease and help the immune system mature. Breastfeeding takes less time, as you simply put the baby to the breast, but feedings will be more frequent, and the baby will grow faster.

Bottle Feeding

The major disadvantage of bottle feeding is the time taken to prepare the bottles, washing, and sterilization. Bottle-fed babies are exposed to a greater risk of becoming infected with organisms that cause vomiting and diarrhea.

Mixed Feeding

Mixed feeding is the combination of breastfeeding and formula. It is an option to complete the natural diet. You may offer a bit of formula after each breastfeeding session or bottle-feed on certain days. Sometimes, mixed feeding is used as a transition to exclusive bottle feeding.

Formula Feeding

Formula milk is designed to replace breast milk. It comes in powder or liquid form and is derived from an industrial process in which cow’s milk is modified to be as close as possible to breast milk. It is much better than unadapted cow’s milk. We start with starter milk (up to 6 months), continue with follow-on milk (to year), and then growth milk (up to 3 years).

Disadvantages of Formula Feeding

  • Sometimes it can overload the baby’s system.
  • Adapted milk, being made from cow’s milk, is more likely to cause allergies.

Advantages of Formula Feeding

  • It does not have to be handled by one person.
  • We know how much milk the baby is drinking.
  • The mother’s feeding habits no longer influence the baby’s intake.
  • The time between feedings may be longer than with breastfeeding, as formula takes longer to digest.

Characteristics of adapted milk formulas:

  • Carbohydrates: Most are lactose.
  • Fat: Cow’s milk fat is replaced by vegetable fats.
  • Proteins: Casein is reduced and replaced by soluble proteins.
  • Vitamins: It provides a fairly complete intake of vitamins.

Equipment for Bottle Feeding

You will need at least 3 or 4 large bottles (250 ml). It’s also good to have extra nipples and keep them in a sterilized container. Other necessary items include:

The Bottle

  • Glass bottles are the most recommended (resistant to high temperatures).
  • They must have graduations (to measure the exact amount).
  • Have one bottle exclusively for water.


  • Choose soft or hard teats to ease suction.
  • The size should be appropriate for the baby’s age and facilitate intake.
  • The most widely used are rubber and silicone, which come in 3 types: anatomical liquid, round liquid, and round food.
  • Use silicone teats in the first months.

Measuring Scoop

  • Adapted milk formulas come with their own measuring scoops (usually 4 or 5 ounces).
  • Use the scoop specific to each product.

Electric Heater

  • Convenient for warming bottles at night or when traveling.

Isothermal or Thermos Bottle

  • Keeps the milk at room temperature for several hours.

Items Required for Hygiene and Sterilization


  • Essential to remove traces of milk from bottles and teats.


  • For handling bottles and nipples after sterilization.


There are several types of sterilizers:


  • Immerse the equipment and boil for 25 minutes in a pot dedicated to that use.


  • Very quick (8 minutes).
  • Comes with compartments to place bottles and teats.
  • Wash the equipment before sterilization to remove milk residue.


  • Submerge the equipment in a container filled with a solution prepared with water and pills or liquid (available at pharmacies).
  • After 1 1/2 hours, the equipment is sterilized.


  • The fastest method.
  • Add a little water to the bottom of the container, place the equipment inside, and microwave on high for 3 to 5 minutes.

Preparation of the Bottle

  1. Use boiled tap water or mineral water.
  2. Pour the boiled water into the bottle, measuring the exact amount.
  3. Use the scoop to measure the amount of water that has been poured (shallow scoops, each 30 cm3 of water requires 1 level scoop of milk).
  4. Pour the powder into the bottle, where it will dissolve easily if the water is hot.
  5. Put on the disc, the ring, and shake.
  6. Verify that the temperature is appropriate (37°C approximately).
  7. If you want to prepare a bottle and save it, close it with the disc and nipple ring and place it face down without touching the milk. It can be stored in the refrigerator for a maximum of 24 hours and kept out for up to 1 hour.

Administration of the Bottle

  1. Test the temperature (37°C) by pouring a few drops on the inside of your wrist (it should be warm).
  2. Check if the milk flow is correct (when overturned, it should drop 2 or 3 drops per second, never spray or drop slower).
  3. Do not overtighten the bottle ring.
  4. Begin feeding, keeping the bottle sufficiently inclined so that the teat is always full of milk and not air.
  5. Feeding should not take more than 20 or 25 minutes.
  6. When finished, burp the baby to expel gases.

Age | Number of Feedings | Amount per Feeding

0-14 days | 7-8 | 60-80 cc

2-6 weeks | 6 | 80-120 cc

2 months | 6 | 120-150 cc

3 months | 5 | 150-180 cc

4-6 months | 4-5 | 180-210 cc

7-9 months | 3-4 | 210-240 cc

10-12 months | 3 | 210-240 cc

How to Introduce New Foods

Complementary Feeding

Complementary feeding is the introduction of new foods other than milk. It starts from 6 months of age.

  • Introduce new foods gradually to avoid digestive problems or allergies.
  • A major change is the introduction of the spoon.
  • Each new food should be introduced in isolation and pureed.
  • Wait at least 24 hours before introducing another new food to observe tolerance.
  • Do not try other new foods until after 1 or 2 weeks to ensure the previous food is tolerated.
  • Continue giving plenty of milk and dairy products, at least 500 ml per day.
  • The baby should drink between 100-150 ml of water per kg of body weight per day.
  • Between 6-9 months, complementary feeding should not exceed 20% of total calories.
  • From 9-12 months, it may reach 30% or 40%.
  • Cook food with little salt and fat, never with seasonings.
  • Start with easily digested foods.
  • Protein-rich foods are not introduced until 9-12 months (as they can cause allergies).

Food Introduction Order

Age | Food

4-6 months | Gluten-free cereals (rice, maize, cassava, and soybean)

5-6 months | Vegetables that are easy on the digestive system (carrots, pumpkin, potato), fruit (apple, banana, pear, and orange), juices

6-8 months | Meats: chicken and veal, ham. Cereals containing gluten (barley, wheat, oats, and rye).

9-11 months | White fish, cookies, egg yolk, yogurt, and cheese

12 months | Whole egg, growth milk, skimmed cow’s milk, lamb, and beef, vegetables, pasta, and soups

From 18 months | Blue fish and seafood, cocoa, other vegetables (spinach, cabbage, cauliflower, and beets), fruits that may cause allergies (strawberries, raspberries, blackberries, peaches)

Proper Diet by Age

Age | Meals

Months 1 and 2 | 6 meals (bottles)

Months 3 and 4 | 5 meals (bottles)

Months 4 and 5 | 5 meals (4 bottles and 1 porridge or mashed food)

Months 5 and 6 | 5 meals (4 bottles and baby food or mashed food)

Months 6 to 8 | 4 meals (mash or puree)

More than 8 months | 4 meals (porridge or mashed food)

If the baby wakes up hungry at dawn, offer a feeding.

From 12-24 months, the daily calorie intake should be 1,000 to 1,100, divided between:

  • Milk and dairy products
  • Meat, fish, eggs (2-3 times per week)
  • Vegetables
  • Fruits
  • Cereals

Offer vegetables 2 times per week.

After 2 years, increase the portions of meat and fish by 30 g each year. All other nutrients should be increased by 15 g.

Development of Feeding Habits

  • Keep the environment calm and quiet throughout the meal (do not lift the baby until they have completely finished eating).
  • Hygiene: Wash hands before and after eating and brush teeth after every meal.
  • Teach habits such as setting the table and clearing it, waiting their turn to be served, not talking while chewing, and proper use of cutlery.
  • Explain how necessary it is to eat slowly, chew, and swallow correctly.
  • Ensure their diet is varied, age-appropriate, and sufficient in quantity and quality.

Possible Eating Disorders

Idiopathic Cramps of the 1st Quarter

  • Digestive distress that appears after or during feeding.
  • The baby suddenly starts to cry, moving and stretching their legs and belly.
  • They disappear by the 3rd month.

Psychogenic Vomiting

  • Vomiting that accompanies intense emotional reactions or oppositional behavior.

Anorexia Nervosa of the 2nd Quarter

  • The baby shows disapproval or disinterest in food.
  • It usually occurs between 5 and 8 months.

Disorders in Elimination

Functional Enuresis

  • Involuntary emission of urine by day or night, at an age when control is expected (beyond 3-4 years).
  • Can be primary (if the child has never achieved bladder control), secondary (if control is lost after a period of being toilet trained), diurnal, nocturnal, or mixed (both times of day).

Functional Encopresis

: is that makes your stools, repeatedly and involuntarily, in places that are not appropriate to the age where they are expected to have control, ie beyond 3-4 years. Can be: primary (if ever control has been achieved), secondary (if it occurs after a control period).