| Number of recognized essential vitamins | 13 (National Institutes of Health, Office of Dietary Supplements) |
| Essential dietary minerals | 16+ (Established nutritional science consensus) |
| Most common micronutrient deficiency globally | Iron deficiency (World Health Organization) |
| Vitamin D synthesis source | Skin exposure to UVB sunlight (National Institutes of Health) |
| Vitamin B12 — primary dietary sources | Animal products and fortified foods (NIH Office of Dietary Supplements) |
What Are Micronutrients?
Micronutrients are the vitamins and minerals your body needs in relatively small amounts to function properly. Unlike macronutrients like carbs, proteins, and fats, micronutrients don't supply energy directly — but without them, your body can't generate or use that energy efficiently. They regulate everything from immune response and bone strength to nerve signaling and hormone production.
Vitamins are organic compounds (made by plants or animals) that your body cannot manufacture in sufficient quantities on its own. Minerals are inorganic elements found in soil and water that enter the food supply through plants and animals. Both categories are classified as essential nutrients — meaning you must obtain them through food or, in some cases, supplementation under medical guidance.
| Number of recognized essential vitamins | 13 (National Institutes of Health, Office of Dietary Supplements) |
| Essential dietary minerals | 16+ (Established nutritional science consensus) |
| Most common micronutrient deficiency globally | Iron deficiency (World Health Organization) |
| Vitamin D synthesis source | Skin exposure to UVB sunlight (National Institutes of Health) |
| Vitamin B12 — primary dietary sources | Animal products and fortified foods (NIH Office of Dietary Supplements) |
For a broader look at how these nutrients fit into your overall eating pattern, see The Science of Eating Well, our complete guide to nutrition fundamentals.
Key Vitamins and What They Do
Vitamins are divided into two groups based on how the body stores them:
- Fat-soluble vitamins (A, D, E, K) are stored in body fat and the liver. Because they accumulate, excessive intake from supplements can reach harmful levels — always consult a healthcare professional before supplementing.
- Water-soluble vitamins (C and the B vitamins) are not stored in large amounts and are excreted in urine, so they need regular replenishment through diet.
Micronutrients
Vitamins and minerals required by the body in small amounts to support essential physiological functions. They do not provide calories but are critical for health and disease prevention.
Fat-Soluble Vitamins
Vitamins A, D, E, and K, which dissolve in fat and are stored in the liver and fatty tissue. Because they accumulate in the body, excessive intake can potentially reach harmful levels.
Water-Soluble Vitamins
Vitamins C and the B-complex group, which dissolve in water and are not stored in significant amounts. They must be regularly replenished through diet, and excess amounts are excreted in urine.
Trace Minerals
Minerals the body needs in very small quantities — including iron, zinc, selenium, and iodine. Despite low required amounts, inadequate intake can cause notable health effects.
Essential Nutrient
A nutrient the body cannot produce in adequate amounts on its own and must therefore obtain through food or supplementation. Both vitamins and minerals fall under this category.
Macrominerals
Minerals required in relatively larger amounts each day, including calcium, magnesium, potassium, phosphorus, and sodium. They support structural roles like bone formation as well as fluid and electrolyte balance.
Fat-Soluble Vitamins at a Glance
| Vitamin | Primary Role | Common Food Sources |
|---|---|---|
| Vitamin A | Vision, immune function, cell growth | Sweet potato, carrots, liver, dairy |
| Vitamin D | Calcium absorption, bone health, immune regulation | Fatty fish, egg yolks, fortified milk; also synthesized via sunlight |
| Vitamin E | Antioxidant protection, immune support | Nuts, seeds, vegetable oils, spinach |
| Vitamin K | Blood clotting, bone metabolism | Leafy greens, broccoli, fermented foods |
Key Water-Soluble Vitamins
| Vitamin | Primary Role | Common Food Sources |
|---|---|---|
| Vitamin C | Collagen synthesis, antioxidant defense, iron absorption | Citrus fruits, bell peppers, strawberries, broccoli |
| B1 (Thiamine) | Energy metabolism, nerve function | Whole grains, pork, legumes |
| B9 (Folate) | DNA synthesis, red blood cell formation | Leafy greens, beans, fortified grains |
| B12 | Nerve health, red blood cell production | Meat, fish, dairy, eggs, fortified plant milks |
Essential Minerals: The Body's Structural and Regulatory Players
Minerals are generally split into macrominerals (needed in larger amounts, such as calcium, magnesium, potassium, and sodium) and trace minerals (needed in smaller quantities, such as iron, zinc, selenium, and iodine). Despite the word "trace," deficiencies in these nutrients can have significant health consequences.
~42%
U.S. adults with vitamin D insufficiency
According to analysis published in Nutrition Research using NHANES data, approximately 42% of U.S. adults have been found to have insufficient vitamin D levels.
2 billion
People affected by micronutrient deficiencies worldwide
The World Health Organization estimates that over 2 billion people globally suffer from micronutrient deficiencies, often called 'hidden hunger.'
| Mineral | Key Function | Food Sources |
|---|---|---|
| Calcium | Bone and tooth structure, muscle contraction, nerve signaling | Dairy, fortified plant milks, leafy greens, tofu |
| Iron | Oxygen transport in red blood cells | Red meat, lentils, spinach, fortified cereals |
| Magnesium | Enzyme activity, muscle and nerve function, blood sugar regulation | Nuts, seeds, whole grains, dark chocolate |
| Zinc | Immune function, wound healing, protein synthesis | Oysters, beef, pumpkin seeds, chickpeas |
| Iodine | Thyroid hormone production, metabolism regulation | Iodized salt, seafood, dairy |
| Potassium | Fluid balance, heart rhythm, muscle function | Bananas, potatoes, beans, leafy greens |
Note that hydration plays a direct role in how well your body absorbs and transports minerals — another reason that water intake and micronutrient status are closely linked.
Getting Enough Through Food — and When to Ask a Doctor
For most healthy adults, a varied diet built around whole foods — fruits, vegetables, legumes, whole grains, lean proteins, and dairy or fortified alternatives — can meet the majority of micronutrient needs. No single food covers everything, which is why dietary variety matters more than any individual "superfood."
Certain groups are at higher risk of specific deficiencies: vegans and vegetarians may need to monitor B12, iron, and zinc; older adults often require more vitamin D and calcium; and people with certain gastrointestinal conditions may have impaired absorption of multiple nutrients. If you fall into a higher-risk group or have concerns about your intake, speak with a registered dietitian or your primary care provider before starting any supplement regimen.
Looking for a concise lookup tool? The Micronutrients at a Glance reference guide covers the vitamins and minerals that come up most in everyday nutrition conversations. You can also explore the full Healthy Eating Basics hub for additional guidance on building a balanced diet.
This article is for general informational and educational purposes only and is not a substitute for professional medical or nutritional advice. Always consult a qualified healthcare provider for guidance specific to your health needs.