The Lowdown on Vitamins

Maggie Grainger
January 21, 2021
7 min read

Vitamins are vital to our overall health and well-being. They help our bodies create energy, break down carbs, transport oxygen, boost our mood, and help our nerves, muscles, immune system, and brain function (and the list goes on and on).

But here’s the catch: Our body doesn’t make vitamins, at least not a significant amount, so we need to get them from our diet. Most healthy adults and children will get the vitamins they need by eating a varied diet rich in fruits, vegetables, and whole grains. In fact, eating a healthy diet is the best way to get your vitamins.

But there may be times you’re running low on a particular vitamin and need to supplement. If your diet is poor, you have a history of alcohol abuse, or your body has trouble absorbing nutrients, you’re at a higher risk of developing a vitamin deficiency. We break some key vitamins, their main functions, and what you can start incorporating into your diet to ensure your body is getting all its essential nutrients.

Key Vitamins: What They Do and Why They’re Important

Vitamin A

Main function: It plays a role in the specialization and growth of every cell in the body and is vital for our vision.

Good sources of Vitamin A: This vitamin comes in two forms: Preformed Vitamin A (Retinol), found in fish, meat, and dairy products, and Provitamin A (Carotenoids), found in fruits and vegetables.

If you’re low in Vitamin A: Vitamin A deficiency is rare in developed countries like the United States, but it manifests as vision problems and even blindness. Worldwide, Vitamin A deficiency causes 250,000–500,000 kids to go blind every year and is the number 1 preventable cause of blindness in kids. Pregnant women who are low in Vitamin A experience night blindness.

Vitamin B1 (also known as Thiamin)

Main function: Turns carbohydrates into energy. Highly recommended for pregnant women.

Good sources of Vitamin B1: Pork, fish, brown rice, whole-grain breads, and pasta

If you’re low in Vitamin B1 Though rare, a common, early sign of B1 deficiency is the loss of appetite and subsequent weight loss. Chronic alcoholism can lead to a severe form of Thiamin deficiency called Wernicke-Korsakoff Syndrome, symptoms of which include extreme confusion, vision problems, and exaggerated storytelling.

Vitamin B2 (also known as Riboflavin)

Main function: This is a key vitamin for your metabolism and energy production.

Good sources of Vitamin B2: It is mostly found in meat, dairy milk, and fortified foods.

If you’re low in Vitamin B2: Deficiencies in B2 most often manifest as pale skin and skin breakdown at the corners of the mouth and lips.

Vitamin B3 (also known as Niacin)

Main function: Helps enzymes carry out chemical reactions throughout the body and may help lower cholesterol.

Good sources of Vitamin B3: Found in fish, turkey, beef, legumes, and nuts.

If you’re low in Vitamin B3: Deficiencies are very rare but common symptoms are memory difficulties, fatigue, headaches, and skin issues. Serious deficiencies can lead to something called Pellagra, or the “4 D Syndrome” characterized by diarrhea, dermatitis, dementia, and death.

Vitamin B5 (also known as Pantothenic Acid)

Main function: Known for helping produce Coenzyme A, a very important molecule involved in the breakdown of fatty acids.

Good sources of Vitamin B5: Found in fish, animal organs, milk, eggs, avocados, and sweet potatoes.

If you’re low in Vitamin B5: Vitamin B5 deficiency is also rare but may include fatigue, insomnia, and stomach pains.

Vitamin B6 (also known as Pyridoxine)

Main function: Mostly involved in amino acid metabolism.

Good sources of Vitamin B6: Found in pork, fish, wheat germ, soybeans, and oats.

If you’re low in Vitamin B6: Deficiencies are rare but present as fatigue, weakness, anemia, and skin rashes.

Vitamin B7 (also known as Biotin or Vitamin H)

Main function: Essential for a wide variety of cellular functions, including glucose metabolism and gene regulation.

Good sources of Vitamin B7: Great sources include egg yolk, walnuts, and organ meats.

If you’re low in Vitamin B7: Biotin deficiencies aren’t common but manifest as breakdowns of the hair and skin.

Vitamin B9 (also known as Folate)

Main function: Important for red blood cell formation and healthy cellular function. It also works with Vitamins B6 and B12 to remove homocysteine, a molecule linked to strokes and heart disease, from the blood.

Good sources of Vitamin B9: Found in green, leafy vegetables, beans, and nuts

If you’re low in Vitamin B9: Most people will get enough folate from their diet, however, pregnant people should supplement with a daily prenatal vitamin. It’s been shown that folate prevents birth defects related to the developing brain and spine.

Vitamin B12 (also known as Cobalamin)

Main function: Helps build nerves, red blood cells and is vital for the metabolism of fatty acids and amino acids.

Good sources of Vitamin B12: Found in meat, eggs, chicken, and dairy products,

If you’re low in Vitamin B12: If someone is deficient in B12, the most common symptoms are strange sensations (like “pins and needles”), tingling in the hands or feet, difficulty walking and maintaining balance, and difficulty thinking and reasoning, sometimes called “brain fog.” You can’t get B12 by eating plants, which is why folks who follow a vegan or vegetarian diet and don’t eat foods fortified with B12, may be at risk of developing a B12 deficiency. A recent study showed that 1 out of 5 vegans were at grave risk of developing a B12 deficiency. People who underwent weight-loss surgery are also at a higher risk.

Vitamin C

Main function: Its main role in the body is connective tissue formation. It is necessary for making collagen, vital for wound healing, and healthy skin.

Great sources of Vitamin C: Red and green peppers and citrus fruits

If you’re low in Vitamin C: If someone is low in Vitamin C, they can develop weakness, fatigue, muscle pain, sore limbs, rough skin, easy bruising, and bleeding of the gums.

Long-lasting Vitamin C deficiency is called scurvy, (the same thing that plagued thousands of sailors in the 1700s until doctors started sending them to sea with bottles of lemon juice). Smokers, and those exposed to second-hand smoke, are often low in Vitamin C, and may want to supplement.

Vitamin D

Main function: This vitamin is vital for bone health at all ages. Vitamin D is also known for its role in preventing upper respiratory infections, and it may even be beneficial in preventing serious COVID-19 infections.

Good sources of Vitamin D: Found in sunshine, red meat, salmon, and milk

If you’re low in Vitamin D: Too little Vitamin D in childhood produces Rickets, or weak, soft bones, and too little in adulthood can lead to porous bones, or Osteopenia. We produce Vitamin D when sunlight directly hits our skin. It’s a fast reaction and doesn’t require much time in the sun. Some people develop deficiencies in the fall and winter months, when there’s not much sunlight, and may want to supplement during that time. Those struggling with obesity and darker-skinned people produce less Vitamin D and may need to supplement more. Also, post-menopausal women may want to supplement because they are at a higher risk of bone problems due to reduced estrogen.

Vitamin E

Main function: This vitamin is best known for its antioxidant abilities. It protects molecules called “free radicals” from damaging cells and may help prevent cancer, heart disease and cognitive decline.

Good sources of Vitamin E: Good sources are nuts, seeds and vegetable oils.

If you’re low in Vitamin E: Deficiencies are uncommon. Vitamin E also inhibits clot formation, which is why supplementation sometimes results in bleeding and puts older people at risk for hemorrhagic strokes.

Vitamin K

Main function: When it comes to clotting, or stopping both internal and external bleeding, Vitamin K is crucial.

Good sources of Vitamin K: Found in spinach, iceberg lettuce, and broccoli

If you’re low in Vitamin K: Deficiencies in Vitamin K result in bleeding and bruising. While rare in adults who get enough from their diet, it is far more common in newborn babies who don’t have enough Vitamin K to form clots. To prevent this, doctors give babies a Vitamin K shot at birth, which protects them. Babies who don’t get the shot are at risk of bleeding complications for up to 6 months.

When Should I Take a Vitamin Supplement?

If you eat a healthy diet, don’t have a malabsorption issue, and aren’t pregnant or breastfeeding, you most likely will get all the vitamins you need from your diet. Babies will need a Vitamin K shot and possibly Vitamin D. Older people, especially those who eat less, may want to supplement. Vegans and Vegetarians may want to supplement with Vitamin B12. If you experience symptoms that you think might be related to a vitamin deficiency, you can supplement on your own or ask your doctor to do a blood test. If you decide to supplement, be sure to purchase vitamins from a trustworthy company with a third-party seal of approval. Also, be aware that supplements can have side effects and interact with prescribed medications. You may unintentionally take more than you need, which can lead to its own health issues.

Is A Multivitamin Better?

Large research studies show that supplementing with a multi-vitamin does not lower one’s risk of heart disease, cancer, or cognitive decline. They aren’t shown to make you live longer than people who don’t supplement. If you are low in a specific vitamin, it’s best to supplement with the specific vitamin.

What About Gummy Vitamins?

Gummy Vitamins differ from traditional multivitamins in that they are made to be tasty and chewable. Because of this, many of them contain added sugars and artificial flavors. They may be beneficial for adults and kids who don’t like to swallow pills, but if you are trying to avoid excess sugar and artificial flavoring, it’s best to avoid these.

Talk to Your Provider About Adding Vitamins to Your Life

The providers at Carbon Health are here to answer any questions you might have about your health. Even if it’s been a minute since you’ve had an appointment or you’re taking steps to establish care through a new clinic, having someone in your corner who you feel comfortable with is key. Take advantage of your next appointment by asking all the questions you need to ask in order to leave the room truly feeling seen, heard, and understood.

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Maggie Grainger

Maggie Grainger is the Brand Copywriter at Carbon Health. She enjoys writing about diverse healthcare issues and helping people live their healthiest lives.


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