What are Vitamins? A Comprehensive Guide to Essential Nutrients


Have you ever wanted to give your body an extra boost but found yourself overwhelmed by the task of figuring out which vitamins you actually need? You’re not alone. 

Although vitamins are essential for your overall health, determining your specific nutritional needs can be challenging.

Nutritional deficiencies can lead to various health complications that impact your health and well-being. That’s why it’s important to educate yourself on which vitamins you need to thrive.

In this article, we’ll take a closer look at the science behind vitamins, where they come from, and why you should be ensuring your body’s needs are met to help you take control of your health. 

What are Vitamins? 

Vitamins are organic compounds that are crucial for the body’s natural growth and maintenance.

Unlike other essential nutrients that fuel the body — such as carbohydrates, proteins, and fats — vitamins are only required in small quantities to provide health benefits.

However, the body can’t produce vitamins naturally, so they must be obtained from dietary sources or supplements.

Types of vitamins 

Vitamins can be divided into two categories based on how they are absorbed and stored in the body. These categories are:

  • Fat-soluble vitamins: These vitamins are absorbed along with fats in the diet and are stored in the liver and fatty tissues. They don’t need to be consumed as much as water-soluble vitamins because the body can rely on these stores. The four fat-soluble vitamins are vitamins A, K, D, E, and K.

  • Water-soluble vitamins: These vitamins aren’t stored in the body, and any excess amounts are excreted in urine. Because of this, we typically need to consume water-soluble vitamins more frequently to ensure we meet the body’s needs. Common water-soluble vitamins include vitamin C and B vitamins.

Common vitamin sources

Vitamin

Natural Sources

Supplements

A

- Liver

- Carrots

- Sweet potatoes

- Kale 

- Retinol (topical use only)

- Beta-carotene 

B1 to B12

-Pork, whole grains, legumes (B1)

- Milk, eggs, almonds (B2)

- Chicken, tuna, avocados (B3)

- Mushrooms, avocados, eggs (B5)

- Fish, potatoes, chickpeas (B6)

- Eggs, almonds, sweet potatoes (B7)

- Leafy greens, beans, citrus fruits (B9)

- Meat, dairy foods, fortified cereals (B12)

- Thiamine mononitrate

- Riboflavin

- Niacin 

- Pantothenic acid

-Pyridoxine

- Biotin

- Folic acid

- Cyanocobalamin 

C

- Citrus fruits

- Strawberries

- Bell peppers

- Ascorbic acid

D

- Fatty fish

- Fortified dairy

- Sunlight

- Cholecalciferol

- Ergocalciferol 

E

- Nuts

- Seeds

- Spinach 

- Alpha-tocopherol

K

- Green leafy vegetables

- Brussels sprouts

- Phytonadione

What are the Health Benefits of Vitamins? 

Supports bone health

Vitamins such as vitamin D and vitamin K are crucial for the development and maintenance of healthy bones.

Vitamin D helps the body absorb calcium — which is essential for strong bones — while vitamin K plays a role in bone development.

Enhances immune function

Vitamins like vitamin C and vitamin A boost the immune system.

Vitamin C enhances the function of immune cells, acting as an antioxidant to protect against damage, while vitamin A strengthens cells that help ward off infections.

Improves brain function 

Several essential vitamins, including the B-vitamins — such as B6, B12, and folate — support brain health.

They aid in the production of neurotransmitters, reduce homocysteine levels — which can harm brain tissue, causing cognitive decline — and maintain healthy brain function.

Boosts energy levels 

B-vitamins — including B1, B2, B3, and B5 — are vital for converting food into energy.

They help metabolize carbohydrates, proteins, and fats, ensuring that our bodies have the energy needed for daily activities.

Improves heart health 

Certain vitamins — such as vitamin E and B-vitamins — can help maintain cardiovascular health.

Vitamin E is an antioxidant that protects cells from damage, while B-vitamins regulate homocysteine levels reducing the risk of heart disease.

Supports eye health 

Vitamin A is particularly important for maintaining healthy vision. It contributes to the production of rhodopsin, a pigment found in the retina that is crucial for seeing in the dark.

This vitamin also helps convert the light that hits the eye into electrical signals that our brain can interpret — the process that helps you to see and make sense of the world around you.

Improves skin and hair health 

Vitamin A, vitamin C, and vitamin B7 (Biotin) play significant roles in maintaining the health of the skin and hair.

Vitamin C is involved in collagen production — which helps the skin appear firm and smooth — while vitamin A helps with cell regeneration to reduce the appearance of fine lines and dark spots.

Biotin helps maintain healthy hair and also promotes hair growth.

Supports red blood cell production

Vitamins B6 and B12 are essential in the production of red blood cells, which carry oxygen to all the organs and tissues in the body.

Adequate levels of these vitamins ensure that the body can produce enough red blood cells to meet its oxygen needs.

Improves digestive health 

Certain vitamins — like vitamin B5 — help support the health of the digestive tract and enhance the absorption of nutrients from your food.

It also helps the body break down fats and carbohydrates, making these nutrients easier to absorb.

Antioxidant protection 

Vitamins — like vitamin C and vitamin E — function as antioxidants. They help protect cells from the damage caused by free radicals, which are linked to chronic diseases and aging.

Key Point: How Should Vitamin Supplements Be Stored?

Proper storage is essential for maintaining the effectiveness of vitamins.

Most dietary supplements containing vitamins and minerals should be kept in a cool, dry place away from direct sunlight.

Supplements that are exposed to heat, moisture, and light can begin to degrade, which may make them less effective.

Avoid storing vitamins in bathrooms or kitchens, where humidity levels are higher and temperatures tend to fluctuate. Instead, opt for the bedroom or living room shelf.

You should also keep vitamins in their original containers with the lids tightly closed to prevent exposure to air.

Vitamin Deficiencies and Health Implications

Common deficiencies

Although vitamins are essential for proper bodily function, deficiencies are quite common — especially if you don’t follow a healthy diet or have poor lifestyle habits, like drinking or smoking. 

Common vitamin deficiencies include:

  • Vitamin D deficiency: This is common in areas where sunlight is limited or among individuals who often use strong sunscreen. It can cause issues like weakness, bone pain, muscle aches, and mood changes.

  • Vitamin B12 deficiency: This deficiency is common among vegetarians and vegans, as well as older adults with nutrient absorption issues. It can cause symptoms like fatigue, dizziness, palpitations, memory issues, and neuropathy (nerve damage).

  • Vitamin C deficiency: Although rare, this deficiency can occur due to a diet low in fresh fruits and vegetables. It can lead to conditions like scurvy or gum disease and may also cause fatigue, bleeding from mucous membranes, and spots on the skin.

  • Vitamin B9 deficiency: This is common in pregnant women and individuals who don’t eat enough leafy greens or legumes. People with this deficiency may experience extreme tiredness, lack of energy, pins and needles (paresthesia), and, in severe cases, anemia. 

If you suspect that you have a vitamin deficiency, consult your doctor as soon as possible for a proper evaluation.

Health risks 

Individuals with vitamin deficiencies may be at risk of developing various health issues, such as:

  • Weakened bones and osteoporosis

  • Neurological issues, such as numbness, tingling in the hands and feet, difficulties maintaining balance, and confusion 

  • Poor memory and dementia 

  • Severe fatigue

  • Poor bone mineralization 

  • Impaired vision 

  • Immune dysfunction 

  • Hair loss (alopecia)

  • Conjunctivitis 

  • Dermatitis 

  • Anemia 

  • Cardiovascular disease and cancer 

  • Perinatal issues, including gestational diabetes and preeclampsia in pregnant women 

  • Diarrhea 

It’s important to note that these health risks may vary, depending on the severity of the deficiency and the specific vitamins you lack. 

Should You Consult Your Doctor About Your Vitamin Intake?

Before increasing your vitamin intake, it’s a good idea to speak to your doctor.

They can help assess your individual needs and suggest the types of vitamins you require as well as your recommended dietary allowance (RDA). 

Your doctor can also monitor your symptoms and make adjustments to your dosages if you develop any adverse effects.

It’s also recommended to consult your doctor in the following circumstances:

  • If you suspect that you have a vitamin, mineral, or nutrient deficiency

  • If you’re worried or unsure about how your medication may interact with an increase in vitamins 

  • If you develop adverse effects after increasing your vitamin intake 

  • If you are pregnant, have specific dietary restrictions, or are over the age of 65

These instances may require a personalized approach to increasing your vitamin intake while avoiding additional health complications, which is why it’s best to speak to your doctor.

Where Can You Learn More About Healthy Lifestyle Habits?

If you’re looking for more information on healthy lifestyle habits to help you improve your overall well-being, LifeMD has got you covered.

A team of medical professionals can guide you on healthy eating habits and teach you how to incorporate sufficient vitamins into your diet.  

Make an appointment with LifeMD to learn more about sustainable ways to take control of your health today.

LifeMD makes it easy to stay on top of your health because talking to a doctor, filling your prescriptions, getting your labs done—and more—are all easy and cost-effective. Come discover a healthcare solution built around you and your life.

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This article is intended for informational purposes only and should not be considered medical advice. Consult a healthcare professional or call a doctor in the case of a medical emergency.

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