1. Protein
Protein acts like the construction worker of the body, helping build and repair tissues such as muscles, skin, hair, and organs. It also forms important molecules like enzymes, hormones, and antibodies, which support metabolism, communication between cells, and immune defense.
When you eat protein, your body breaks it down into amino acids, the building blocks of protein. There are 20 amino acids in total, and 9 of them are essential, meaning the body cannot produce them on its own and must obtain them from food.
Common protein-rich foods include chicken, fish, eggs, Greek yogurt, beef, lentils, tofu, chickpeas, quinoa, and almonds.
Proteins that contain all nine essential amino acids are called complete proteins. Most animal-based proteins are complete, while many plant-based proteins are incomplete. However, eating a variety of plant foods such as beans, grains, nuts, and seeds throughout the day may provide all the essential amino acids your body needs.
2. Fats
Fats are an essential nutrient that play several important roles in the body. They help form cell membranes, protect and cushion internal organs, and provide a long-lasting source of energy.
Dietary fat is also necessary for absorbing fat-soluble vitamins, including vitamins A, D, E, and K, which the body cannot properly absorb without fat.
Healthy sources of fat include avocados, olive oil, nuts such as almonds and walnuts, seeds like chia and flax, and fatty fish.
However, some fats are less beneficial for health. Trans fats and highly processed fats have been linked to an increased risk of heart disease and should be consumed in limited amounts.
3. Vitamins
Vitamins are nutrients your body needs in small amounts, but they play essential roles in maintaining health and supporting many biological processes.
There are 13 essential vitamins, which are divided into two groups:
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Fat-soluble vitamins: A, D, E, and K
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Water-soluble vitamins: Vitamin C and the B-complex vitamins
Vitamin A
Vitamin A helps maintain healthy vision, supports the immune system, and promotes proper cell growth.
Common food sources include carrots, sweet potatoes, spinach, and animal liver.
Vitamin D
Vitamin D helps the body absorb calcium, which keeps bones and teeth strong. The body can produce vitamin D when skin is exposed to sunlight, and it can also be obtained from foods like fatty fish, egg yolks, and fortified milk.
Vitamin E
Vitamin E acts as an antioxidant, helping protect cells from damage caused by harmful molecules known as free radicals. Good sources include almonds and sunflower seeds
Vitamin K
Vitamin K plays a key role in blood clotting and also supports bone health. It is commonly found in leafy green vegetables such as kale, broccoli, and Brussels sprouts.
Vitamin C
Vitamin C supports the immune system, helps the body heal wounds, and is essential for producing collagen, a protein that maintains healthy skin and tissues.
Good sources include oranges, lemons, bell peppers, kiwi, and broccoli.
Vitamin B Complex
The B-complex vitamins are like a coordinated team (or a “boy band”), working together to help the body produce energy, support brain function, and create red blood cells.
There are eight B vitamins, and they can be found in foods such as whole grains, meat, eggs, leafy greens, legumes, and nutritional yeast.
There are 8 B vitamins:
B1 Thiamine
B2 Riboflavin
B3 Niacin
B5 Pantothenic acid
B6 Pyridoxine
B7 Biotin
B9 Folate
B12 Cobalamin
4. Minerals
Minerals are essential nutrients that the body needs to support many important functions, including bone health, nerve signaling, muscle function, and fluid balance.
Minerals are generally divided into two groups: major (macro) minerals and trace minerals.
Major (macro) Minerals
Generally needed in larger amounts
- Calcium
- Phosphorus
- Magnesium
- Sodium
- Potassium
Major minerals are required in relatively larger amounts. These include calcium, phosphorus, magnesium, sodium, potassium, and chloride.
Calcium and phosphorus are essential for building and maintaining strong bones and teeth. Common sources include milk, cheese, yogurt, and leafy green vegetables.
Magnesium supports muscle relaxation, nerve function, and energy production. It can be found in foods such as pumpkin seeds, almonds, spinach, black beans, and dark chocolate.
Sodium and potassium help maintain fluid balance in the body and play an important role in nerve signaling and muscle contraction.
Potassium-rich foods include bananas, potatoes, and avocados.
Trace Minerals
Needed in very small amounts
- Iron
- Zinc
- Iodine
- Selenium
- Copper
- Manganese
- Chromium
- Fluoride
- Chloride
- Sulfur
Trace minerals are needed in very small amounts, but they are still essential for health.
Iron helps red blood cells carry oxygen throughout the body. Good sources include red meat, beans, and fortified cereals.
Zinc supports the immune system, wound healing, and cell growth. It can be found in oysters, beef, pumpkin seeds, and chickpeas.
Iodine is necessary for producing thyroid hormones that regulate metabolism. Common sources include iodized salt, seaweed, fish, and dairy products.
Selenium acts as an antioxidant and supports thyroid function. It is found in foods like Brazil nuts, seafood, and whole grains.
5. Carbohydrates
Carbohydrates are the body’s main source of energy. When you eat carbohydrates, the digestive system breaks them down into glucose, which cells use as fuel to power the brain, muscles, and other organs.
Common carbohydrate-rich foods include pasta, bread, rice, potatoes, oats, quinoa, and fruits such as bananas and apples.
Carbohydrates are generally divided into two main types:
Simple carbohydrates
Simple carbohydrates are sugars that the body digests quickly, providing a rapid source of energy. Examples include sugary foods, honey, and soda.
Complex carbohydrates
Complex carbohydrates are made of longer chains of sugar molecules and take longer to digest, providing more sustained energy. They are commonly found in whole grains, oats, quinoa, legumes, and starchy vegetables.
Foods rich in complex carbohydrates often also contain fiber, which supports digestive health and helps regulate blood sugar levels.
Fiber
Fiber is a type of carbohydrate that the body cannot fully digest, but it plays an important role in maintaining digestive health.
There are two main types of fiber:
Soluble fiber dissolves in water and forms a gel-like substance in the digestive tract. It helps slow digestion, regulate blood sugar levels, and lower cholesterol.
Insoluble fiber does not dissolve in water and helps move food through the digestive system, supporting regular bowel movements.
Fiber also feeds beneficial bacteria in the gut, which supports overall digestive health.
Additional Notes:
Water
Water is essential for life and makes up about 60% of the human body.
It plays many critical roles, including:
Regulating body temperature
Transporting nutrients, oxygen, and hormones in the blood
Removing waste products from the body
Supporting digestion and cellular function
Drinking enough water helps keep the body properly hydrated and functioning efficiently.
Antioxidants
Antioxidants are not a nutrient category like vitamins or minerals.
They are compounds found in many foods that protect cells from oxidative stress.
Examples:
Vitamin C
Vitamin E
Beta-carotene
Selenium
Flavonoids
Polyphenols
Antioxidants are compounds that help protect the body against free radicals, unstable molecules that can damage cells and contribute to aging and disease.
Common antioxidants include vitamin C, vitamin E, beta-carotene, selenium, flavonoids, and polyphenols.
Foods rich in antioxidants include colorful fruits such as blueberries, blackberries, and strawberries, as well as dark green vegetables, green tea, tomatoes, and sweet potatoes.