Vitamins and Minerals: What They Are and Why Your Body Can't Function Without Them
Key Takeaways
Start here
What Are Vitamins and Minerals?
Understand the difference
How Vitamins and Minerals Differ From Each Other
Recognize the signs
What Happens When You Don't Get Enough
Find your sources
The Best Food Sources for Key Micronutrients
Take action
Practical Steps to Improve Your Micronutrient Intake
What Are Vitamins and Minerals?
Vitamins and minerals are nutrients your body needs to carry out thousands of processes every day — from converting food into energy to repairing tissues and supporting your immune system. Unlike carbohydrates, proteins, and fats, which are called macronutrients, vitamins and minerals are classified as micronutrients because the body requires them in comparatively small amounts. Small, however, does not mean unimportant. Even tiny shortfalls can have measurable effects on how you feel and function.
Your body cannot manufacture most vitamins and minerals in sufficient quantities on its own, so food is the primary delivery system. This is one reason nutrition scientists consistently emphasize dietary variety — no single food provides every micronutrient you need.
To learn how micronutrients fit into the bigger picture of a healthy diet, see our Balanced Diet Basics hub.
Micronutrient
A nutrient the body needs in small amounts — including all vitamins and minerals — to carry out essential biological processes.
Fat-soluble vitamin
A vitamin (A, D, E, or K) that dissolves in fat and can be stored in the body's tissues, meaning both deficiency and excess can develop over time.
Water-soluble vitamin
A vitamin (C or any of the B vitamins) that dissolves in water and is not stored in large amounts, so regular intake through food is important.
Trace mineral
A mineral the body needs in very small quantities — such as zinc, iron, or selenium — that is still essential for normal health.
Deficiency
A state in which the body does not have enough of a specific nutrient to perform its normal functions, which can lead to recognizable health symptoms over time.
Bioavailability
How well the body can absorb and use a nutrient from a particular food or supplement — some forms of a nutrient are absorbed more efficiently than others.
How Vitamins and Minerals Differ From Each Other
Although vitamins and minerals are often mentioned together, they are chemically distinct.
Vitamins are organic compounds, meaning they contain carbon and are originally made by living things — plants, animals, or bacteria. There are 13 essential vitamins. They are further grouped by how the body stores them:
- Fat-soluble vitamins (A, D, E, and K) dissolve in fat and can be stored in body tissues for later use.
- Water-soluble vitamins (vitamin C and the eight B vitamins) dissolve in water. Because they are not stored as readily, you need a consistent supply from food.
Minerals are inorganic elements — they come from the earth, absorbed by plants and passed along through the food chain. They are divided into two categories based on how much the body needs:
- Major minerals (such as calcium, magnesium, and potassium) are needed in larger amounts and play central roles in bone structure, fluid balance, and muscle function.
- Trace minerals (such as iron, zinc, and selenium) are needed in smaller quantities but are no less essential.
For a quick-reference breakdown of key minerals, see Essential Minerals at a Glance.
What Happens When You Don't Get Enough
Deficiencies develop gradually. Early symptoms are often vague — fatigue, difficulty concentrating, or feeling run-down — which makes them easy to overlook or attribute to other causes. Over time, specific shortfalls produce more recognizable signs:
- Iron deficiency can lead to anemia, leaving you feeling exhausted and short of breath.
- Vitamin D deficiency is linked to weakened bones, low mood, and impaired immune function.
- Vitamin C deficiency, if prolonged, can cause poor wound healing and, in severe cases, scurvy — though this is rare in the U.S. today.
- Magnesium deficiency may contribute to muscle cramps, poor sleep, and elevated blood pressure.
Don't Self-Diagnose or Self-Treat Deficiencies
Many deficiency symptoms — fatigue, brain fog, muscle weakness — overlap with dozens of other health conditions. Taking high-dose supplements without confirmed deficiency can sometimes cause harm, particularly with fat-soluble vitamins that accumulate in the body. If you're concerned about your nutrient status, speak with a healthcare provider who can order appropriate tests.
Symptoms like these overlap with many other health conditions. Only a licensed healthcare professional can diagnose a deficiency through proper testing. If you suspect a deficiency, do not self-treat with high-dose supplements — consult your doctor first.
For a practical checklist of physical signals worth discussing with your provider, visit Signs Your Diet May Be Missing Key Micronutrients.
The Best Food Sources for Key Micronutrients
Whole, minimally processed foods are consistently the most reliable micronutrient sources because they deliver nutrients in combinations the body recognizes and absorbs efficiently. Here is a practical overview:
| Nutrient | Key Food Sources |
|---|---|
| Vitamin A | Sweet potatoes, carrots, spinach, eggs |
| Vitamin C | Bell peppers, citrus fruits, broccoli, strawberries |
| Vitamin D | Fatty fish, fortified dairy or plant milks, egg yolks |
| Calcium | Dairy products, fortified alternatives, kale, almonds |
| Iron | Lean red meat, lentils, tofu, fortified cereals |
| Magnesium | Pumpkin seeds, black beans, whole grains, dark chocolate |
| Zinc | Oysters, beef, chickpeas, cashews |
Eating a wide variety of foods across all food groups over the course of each week is more effective than focusing on any single superfood.
Practical Steps to Improve Your Micronutrient Intake
You do not need to overhaul your diet overnight. Small, consistent changes compound over time.
- Eat by color. Different pigments in fruits and vegetables signal different nutrients. Aim to include at least three distinct colors on your plate each day.
- Choose whole over refined. Whole grains retain the bran and germ, which are rich in B vitamins and minerals stripped away during refining.
- Include legumes regularly. Beans, lentils, and chickpeas are affordable, versatile sources of iron, magnesium, folate, and zinc.
- Pair iron-rich plant foods with vitamin C. Vitamin C helps the body absorb non-heme iron (the form found in plants) more effectively. For example, add lemon juice to a lentil salad.
- Limit ultra-processed foods. These are often calorie-dense but micronutrient-poor, crowding out more nutritious options.
Start With One Meal, Not Your Whole Diet
Trying to change everything at once is a common reason people give up on healthier eating. Instead, identify one meal each day where you can add a serving of vegetables, swap refined grains for whole grains, or include a legume. Once that feels normal, build from there.
Men in particular tend to fall short on several key micronutrients. Our article on nutrients most men don't get enough of covers the most common gaps and why they matter.
This article is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider with any questions you may have about your nutritional needs or health.