Nutritional Eating: A guide to Vitamins

The human body requires several different nutrients in order to function efficiently. This range is often divided into 2 parts - Macro and Micro nutrients. The first group is made up of Carbohydrates, Fats, and Proteins. They are responsible for sustaining and providing energy to the body, and are needed in large amounts. On the other hand, the Micro group is comprised of the other nutrients, which are consumed in comparatively smaller amounts, serve the body in different ways, and help us derive the energy needed from the macro nutrients. It is extremely essential to understand the importance of eating a variety of micro nutrients in daily life, out of which we will discuss Vitamins.

Vitamins

There are 13 Vitamins namely; Vitamin A, B (there are 8 sub-types), C, D, E, and K.

Out of these, Vitamins A, D, E, and K are fat-soluble, which means they dissolve in fat and are stored in the body, while the B sub-types and C Vitamins are water-soluble, which means they dissolve in water, and the excess is flushed out (implying that you need new supply every day). Each of these vitamins are important for the body in their own way.

Vitamin A

Forms/Types

Vitamin A is found as either Preformed Vitamin A or Provitamin A Carotenoids. Preformed Vitamin A is already present in foods, while Provitamin A Carotenoids are *Carotenoid pigments which the body converts into Vitamin A.

*Carotenoid pigments are derived from some yellow, orange, and red-colored fruits or vegetables.

Importance and Benefits

Vitamin A serves many different purposes to the body. This nutrient is known to:

1. Make the immune system stronger

2. Maintain healthy skin

3. Enhance Vision

4. Help growth and reproduction

5. Aid with cell division

6. Contributes to function of heart, lungs, and other organs

7. Have antioxidant properties protecting cells from free radicals (which can cause diseases)

In addition to these benefits, research has also pointed towards Vitamin A lowering severity and chance of death from Measles, as well as helps slow vision loss to an extent for Age-related Macular Degeneration (AMD).

Sources

• Fish such as Salmon

• Organ Meats such as liver (not recommended in large amounts due to high cholesterol)

• Dairy Products

• Fortified Breakfast Cereal

• Eggs

• Fruits (Orange) like Mangoes, Apricots, and Cantaloupe

• Green Leafy Vegetables

• Green, Orange, and Yellow Vegetables (i.e Broccoli, Carrots, etc)

  
  

  Many of these sources, in addition to several Vitamin A supplements have Beta-Carotene, which is converted to Vitamin A within the body.

Deficiency

Vitamin A deficiency is pretty uncommon in the US. Those in developing countries are most vulnerable, in addition to certain groups including: Premature Infants, Infants/Kids, Pregnant/Breastfeeding Women, and people with cystic fibrosis, Crohn's disease, ulcerative colitis, or celiac disease. Some possible effects of Vitamin A deficiency are:

1. An eye condition called Xerophthalmia; difficulty seeing in low light and can lead to being blind without treatment

2. Increased risk of respiratory diseases and infections

3. Can cause anemia (red blood cells don't supply enough oxygen)

4. Increased risk of dying in extreme cases

5. Too much keratin in the skin

Intake Amount Recommended for adults

900 mcg for men and 700 mcg for women is recommended daily

Vitamin B - the 8 sub-types

B1 [Thiamine]

Importance - Turns glucose into energy; participates in nerve function

Sources - Wholemeal cereal grains, sesame seeds, legumes, nuts, etc.

Deficiency - More common in countries with white rice as their staple, and in the west, is linked to alcohol intake and unbalanced diet.

• Symptoms:

  • Confusion

  • Irritability

  • Fatigue

• Conditions cause by Thiamine deficiency:

  • Beriberi - condition affecting cardiovascular, muscular, gastrointestinal, and nervous systems. Can be "dry" or "wet"; "dry" affects the nervous system, "wet" affects the cardiovascular system

  • Wernicke-Korsakoff syndrome - related to alcohol and thiamine-deficient diets. Reduction of thiamine absorption in the gut and increase in excretion from the kidney occurs because of the alcohol.

Intake Amount Recommended for adults - 1.2 mg daily

B2 [Riboflavin]

Importance - Mainly helps energy production and aids vision and skin health

Sources - Milk, yogurt, cottage cheese, whole grain bread and cereal, etc.

Deficiency - Rare and usually accompanies other Vitamin B deficiencies. People drinking too much alcohol or those on diets without milk or milk products (vegans) are at the highest risk

Intake Amount Recommended for adults - 1.3 mg daily

B3 [Niacin]

Importance - necessary for the body to turn carbs, fat, and alcohol into energy. Helps keep healthy skin, aids the nervous and digestive systems. Niacin is heat stable, and most is sustained even after cooking.

Sources - fish, milk, wholegrain bread and cereals, nuts, all protein-containing food, etc.

Deficiency - Niacin deficiency is called Pellagrra. People who drink excessively or survive on corn-based diets are at the greatest risk. Digestion problems where niacin can't be digested properly may also be another reason for risk. Dementia, Diarrhoea, and Dermatitis are symptoms of Pellagra, and this condition can lead to death if not treated.

Intake Amount Recommended for adults - 16 mg daily

B5 [Pantothenic acid]

Importance - necessary for metabolizing carbs, proteins, fats, and alcohol. Also used to make red blood cells and steroid hormones.

Sources - meats, milk, peanuts, legumes, etc.

Deficiency - As found in so many foods, this deficiency is extremely rare.

Intake Amount Recommended for adults - 5 mg daily

B6 [Pyridoxine]

Importance - essential for protein and carbs metabolism, making of blood cells and certain brain chemicals

Sources - Cereal grains, legumes, fruit, nuts, etc.

Deficiency - This deficiency is rare. The highest risk is to those who excessively drink,

are women (on the contraceptive pill), seniors, or those with thyroid.

Intake Amount Recommended for adults - 1.7 mg daily

B7 [Biotin]

Importance - necessary for energy/amino acid metabolism and fat/glycogen synthesis.

Sources - cauliflower, peanuts, mushrooms, etc.

Deficiency - Very rare since needed in small amounts and widely distributed. Can be induced if raw egg whites are over-eaten over several months by either athletes/bodybuilders, as its protein prevents Biotin absorption.

Intake Amount Recommended for adults - 30 mcg daily

B9 or Folate / Folic acid

Importance - used to form blood cells. It also helps with the developing of the foetal nervous system, and DNA and cell growth. Therefore women who are of age to bear a child should ensure eating folate for this reason. It is especially important to have enough folate during pregnancy to reduce risk of neural tube defects for the baby.

Sources - Green leafy vegetables, legumes, citrus fruits, seeds, cereals, etc.

Intake Amount Recommended for adults - 400 mcg daily

B12 [Cyanocobalamin]

Importance - Aids in production and maintenance of myelin around nerve cells, mental ability, and the creation of red blood cells, and breading down some fatty/amino acids to create energy. Closely relates to folate; depending on each other to function.

Sources - meat, milk, eggs, and most anything with an animal origin.

Deficiency - As B12 comes from animal products, vegans and vegetarians are most likely to have this deficiency. Also, since absorption decreases with age, seniors are at risk of this deficiency as well. Therefore, seniors, vegans, and vegetarians are encouraged to take special care of their B12 levels, and take additional supplements if their daily needs aren't getting fulfilled with their diet.

Intake Amount Recommended for adults - 2.4 mcg daily

Vitamin C

Importance and Benefits

Vitamin C is extremely important, and works for the following causes:

1. Essential and helpful to making blood vessels, cartilage, muscle, and collagen in the bone

2. Assists in the body's (wound) healing process

3. It is an antioxidant and helps protect cells from free radicals (coming from breaking down food, sun, x-rays, etc), which are often associated with heart disease, cancer, and others

4. Aids with absorbing and storing Iron inside the body

5. Controls infections

Also, Vitamin C has been said to prevent Age-related Macular Degeneration (AMD) from becoming worse. Some studies have also pointed to a vitamin C -rich diet lessening the possibility of developing cataract.

Sources

• Citrus Fruits - Oranges, Lemon, Grapefruit, etc.

• Berries - Strawberries are most notable

• Potatoes

• Tomatoes

• Bell Peppers

• Cruciferous Vegetables - Cabbage, Brussels Sprouts, Broccoli

• Spinach

• Cantaloupe

  
  
  
  

  Vitamin C can also be eaten in the form of supplements.

Deficiency

People don't usually have a Vitamin C deficiency as it can get fulfilled with a balanced diet. But some groups of people are susceptible to getting this deficiency, including: people who smoke or secondhand smoke, have certain conditions or cancer, and people that don't usually eat fruits or vegetables in their diet. Vitamin deficiency can occur if eating 10 mg or less of Vitamin C daily for 1+ month. Effects of this deficiency:

1. Scurvy: A severe enough deficiency can cause one to obtain the Scurvy disease, which causes [Iron-deficiency] Anemia, bleeding gums, bruising, less power to heal wounds, fatigue, overall tissue weakness, capillary becoming fragile, skin spots, and hair loss.

Intake Amount Recommended for adults

90 milligrams for men and 75 milligrams for women (adults) daily

Vitamin D

Forms/Types

Vitamin D can be either already present in food sources, added to some foods, or generated through synthesis when UV rays from the sun touch the skin.

Importance and Benefits

Vitamin D does much to help us, including:

1. Helping us build and maintain healthy bones by allowing the absorption of Calcium

2. Enhancing the immune function, muscles, and brain cell activity due to its anti-inflammatory, antioxidant, and neuroprotective nature

3. Helping growth and reproduction

4. Aiding with glucose metabolism

Additionally, research has said that getting enough Vitamin D can help prevent bone conditions such as osteoporosis, as it mainly helps strengthen the bones.

Sources

Note: It isn't naturally found in many foods, so many fortified foods do include Vitamin D.

• UV rays from the sun (in the morning time)

• Fortified milk

• Fortified Cereal

• Fatty Fish like Salmon

• Egg yolks

• Cheese

• Mushrooms

• Fortified Yogurt and juices

• Liver meats

  Vitamin D can be taken as supplements as well, which is often a good idea if your diet doesn't include much Vitamin D and/or you can't get enough Vitamin D from the sunlight due to your routine or location in the world.

Deficiency

Vitamin D deficiency is actually very common, and impacts people based on several factors. The first one would be skin color. People with darker skin have more trouble generating Vitamin D from UV rays than those with lighter skin, and therefore are more probable to have Vitamin D deficiency. Another factor would be where one lives. People in middle eastern areas with multiple coverings get less exposure to sunlight, while people in the Arctic naturally don't get light for 1/2 the year! In total, according to my.clevlandclinic.org, around 1 billion people around the world have this deficiency, and specifically for the US, 35% adults lack the appropriate amount of Vitamin D. This deficiency can have several effects, such as:

1. For infants and children,Vitamin D deficiency can lead to rickets, a disease in which bone tissue can't properly mineralize, which leads to soft bones and skeletal deformities. "Severe rickets can cause failure to thrive, developmental delay, hypocalcemic seizures, tetanic spasms, cardiomyopathy, and dental abnormalities" according to https://ods.od.nih.gov/

2. Similar to rickets, osteomalacia can occur in adults and youth. This is when the bone tissue doesn't fully and/or properly mineralize when being remodeled, leading to weak bones. The symptoms are almost the same to rickets, which are mentioned above

3. People with this deficiency can feel fatigue and mood swings, as well as bone pain and cramps

Vitamin D supplements, a good diet, and adequate time in the sun are ways to fulfill your Vitamin D needs and refrain from having such deficiency.

Intake Amount Recommended for adults

600 IU (international units) ~ 15 mcg of Vitamin D are recommended to be daily consumed/taken by adults

Vitamin E

Importance and Benefits

The nutrient Vitamin E is known to:

1. Be important for vision and reproduction

2. Maintain healthy blood, brain, and skin

3. Have antioxidant properties protecting cells from free radicals (which can cause diseases)

   
   

In addition to these benefits, research has also pointed towards Vitamin E possibly being able to slow the progression of Alzheimer's Disease with a high dosage. But, something to note is that the use of Vitamin E supplements may be linked with increased risk of prostate cancer, but this is not fully confirmed to be the case.

Sources

• Canola, Sunflower, Soybean, and Olive oil

• Margarine

• Almonds and Peanuts

• Meats

• Green Leafy Vegetables

• Fortified Cereals

• Sunflower Seeds

• Red Bell pepper

• Mangoes

• Avocados

  Vitamin E supplements are also available, but note that they are less healthier and may be related to prostate cancer somehow.

Deficiency

As Vitamin E is widely found in foods, it is pretty rare in the United States. People with digestive disorders or are unable to absorb fat are at risk. Some effects and signs are:

1. Nerve pain / Peripheral neuropathy

2. Retinopathy - damage to retina and can impair vision

3. Ataxia - loss of body control

4. Decreased immunity

Intake Amount Recommended for adults

15 milligrams of Vitamin E per day is recommended for adults

Vitamin K

Forms/Types

Vitamin K is mainly found as phylloquinone, the other type being menaquinones.

Importance and Benefits

Vitamin K has many roles in the body, but the primary ones would be to make proteins needed for blood clotting and building/strengthening bones. The blood clotting is what helps heal injuries, and prevent/stop life-threatening bleeding. In fact, Vitamin K is essential in making 4 of the 13 proteins essential for making blood clots! As for the strengthened bones, since the vitamin allows the protein osteocalcin to be created, bones become strong and avoid low density, which can possibly reduce the risk of further bone problems. Some other functions of Vitamin K include:

• Easing morning sickness

• Protecting cognitive functions

• May protect heart's health

Sources

Phylloquinone (K1 - The main one)

• Green Leafy Vegetables - turnip greens, spinach, broccoli, cabbage, lettuces

• Soybean and Canola Oils

• Salad dressings with Soybean or Canola

• Blueberries

Menaquinones (K2)

• Animal products

• Fermented foods - Natto (fermented Soybean)

• To an extent in Meat, Cheese, and Eggs

• Produced by bacteria in the gut

Supplements are available, but aren't necessary to be taken as the required Vitamin K can easily be derived from food sources.

Deficiency

Vitamin K deficiency is pretty rare due to it's wide availability through food sources. Newborns are a group at risk of this deficiency due to transfer from the placenta to breast milk. Other people at risk would be those who either: have a disease affecting the digestive tract, are taking interfering medications, are severely malnourished, or drink a lot of alcohol. In any case, Vitamin K deficiency has symptoms like:

1. Feeling Sleepy

2. Seizures

3. Bruising

4. Jaundice or Pale skin

5. Throwing up

6. Nosebleeds

7. Bloody, sticky, dark stool

8. Small red spots

Intake Amount Recommended for adults

120 mcg for men and 90 mcg for women is recommended daily

In conclusion, Vitamins impact your body in many different ways, and are extremely important for you. Therefore, it is important to ensure a balance of these Vitamins in your daily diet and stay healthy!

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Assessed and Endorsed by the MedReport Medical Review Board