Basics of Nutrition

Macronutrients are the essential building blocks and energy carriers for the body. Without them, our body can quickly wither away and are critical to our living and health. You need plenty of these to stay healthy and nourished. There are three different types of macronutrients: Proteins, Carbohydrates and Fats.

Carbohydrates are molecules that can be used as fuels by turning into simple sugars that can be used as fuel for the body.

Major sources: Sugars, starches, grains, vegetables and fruits. These sources can be further refined to create sugars and syrups.

There are different types of carbohydrates and the sum of them is called 'Total carbohydrates'.

• Simple carbohydrates: They are basic forms of carbohydrates that easily and rapidly break down into simple sugars. These may be added to candies, desserts and soda but may be found in fruits, milk and vegetables as well. These added forms are called 'Added sugars'.
• Complex carbohydrates: Also known as starches, these are strung up simple carbohydrates that eventually are broken down by our body to simple sugars to be digested and used as fuel or for storage.
• Dietary fiber: Fibers are part of plants and can be either soluble or insoluble. They give plants their rigid structure and can slow down or prevent nutrients from being digested in the body by binding around them. Soluble fibers dissolve in water while insoluble fiber does not and is fermented by the bacteria in our intestines. Both are tolerable and may be useful in small amounts. They can be found in nuts, fruits, vegetables, beans, grains and various plants.
• Sugar alcohols: These are sweet substances that are added to food products to make them sweeter without the extra energy that comes with other forms of carbohydrates. They are well tolerated in low amounts. Examples include Xylitol and Erythritol.

Fats are another source of fuel for the body and are prioritized to be burnt when consumption of carbohydrates is restricted or totally removed. These fats are converted into Ketone bodies which are further used to fuel the body.

Major sources: Animal products, nuts and seeds. These sources can be further clarified to make butters, ghee, tallow and various oils.

There are different types of fats as well and the sum of all these fats is called ‘Total fat’.

• Saturated fats: These are normally solid at room temperature and are found in foods such as milk, cheese and various meats but may be isolated from plants to create coconut oil, palm oil, cocoa butter and butter.
• Trans fats: These are fats that have undergone hydrogenation which increases their shelf life and are harder at room temperature.
• Unsaturated fats: These are usually liquids at room temperature and common in many plants:
  • Monounsaturated fats: Found in foods such as avocados, nuts and vegetable oils.
  • Polyunsaturated fats: They are found in vegetable oils such as safflower, sunflower, sesame, corn oils and seafood:
    • Omega-3 fatty acids: They are found in soybean oil, canola, walnuts, flax seeds, salmon, herring, anchovies, herring, sardines, trout, mackerel and shellfish as eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA).
    • Omega-6 fatty acids: They are found in liquid vegetable oils such as soybean oil, corn oil and safflower oil.

They form the building blocks of the body. During the day, body takes wear and tear and needs to be repaired. Proteins help with this process while serving as raw materials for creating new muscles. Though proteins can come from plant and animal sources, plant sources normally have to be fortified or supplemented in order to make yield a complete source of essential amino acids.

Major sources: Meat, eggs, cheese, soy and nuts. These sources can be further isolated to make protein isolates and powders.

• Essential Amino Acids: These must be obtained from the diet.
  • Phenylalanine
  • Valine
  • Tryptophan
  • Threonine
  • Isoleucine
  • Methionine
  • Histidine
  • Leucine
  • Lysine
• Non-Essential Amino Acids: The body produces these itself.
  • Alanine
  • Arginine
  • Asparagine
  • Aspartic acid
  • Cysteine
  • Glutamic acid
  • Glutamine
  • Glycine
  • Proline
  • Serine
  • Tyrosine
• Conditionally-Essential Amino Acids: These are ones that your body can't produce under illnesses or stressful circumstances.
  • Arginine
  • Cysteine
  • Glutamine
  • Tyrosine
  • Glycine
  • Ornithine
  • Proline
  • Serine

All macronutrients contribute towards providing our body with energy which is measured in calories(kcal), similar to how distance is measured in meters. In simplicity, pure fats, carbohydrates and proteins provide 9, 4 and 4 calories per gram, respectively. Dietary fibers and sugar alcohols usually have very low, none or negligible energy in them. Therefore, they are subtracted during calculations of total energy inside the food.

Every person has a set amount of energy that they need to consume to maintain their current weight. Going underneath usually results in weight decrease while going above usually results in weight increase.

It is important to note that simple calorie calculations are estimates and can fluctuate depending on the food type. However, this method gives us a good idea on the energy contained inside such foods.

Micronutrients are essential substances that are required in trace amounts to help regulate several processes in our body and to maintain adequate health. They are equally as critical for health though their requirements are far lower. Due to their importance, there is a Recommended Daily Allowance(RDA) for these micronutrients. There are two types of micronutrients: vitamins and minerals.

Vitamins are organic compounds made by plants and animals which break down in the body to help regulate and enable many processes such as production and release of energy in the body and cell formation and brain function. They can be found in both plants and animals such as meats, fish, dairy, fruits, beans and grains. Vitamins are either water-soluble or fat-soluble. Water soluble vitamins are flushed and need to be replenished while fat soluble vitamins are taken up and used in the body for various processes.

Many nutrition labels may not have full details on vitamin content.

Values Extracted from Harvard Health

Minerals are inorganic compounds that have several roles in the body depending on the type of mineral ranging from growth, healing, immune function, protection against oxidative damage, creation of hormones and so on.

Many nutrition labels may not have full details on mineral content.

Values Extracted from Harvard Health

These components in food can change the way food can look or feel. Some of them can make the food become thicker, gel-like or emulsify two substances together.

Aromas are what add a blissful or repulsive smell to foods depending on what is added to the food or whether the food is in the process of decaying. Everyone wants something that smells good!

Coloring agents are naturally existing compounds or synthesized to give the food a more vibrant and attractive look.

Food flavors can be either sweet, umami, salty, sour, spicy or bitter. Each of these are mainly detected by our tongue when foods are eaten. They can make foods more joyful and palatable or can make them repulsive!