Vitamins and Minerals: A No-Jargon Reference

What Are Vitamins and Minerals?

Unlike proteins, carbohydrates, and fats, vitamins and minerals are micronutrients — compounds your body needs in small amounts but cannot manufacture in sufficient quantities on its own. They don't provide energy directly, but they make nearly every biological process possible: turning food into fuel, building bone, transmitting nerve signals, and defending against infection.

Vitamins are organic compounds, meaning they come from living sources and can be broken down by heat, air, or acid. Minerals are inorganic elements — think calcium, iron, and zinc — that hold their structure through cooking and digestion. Both categories are essential, and a shortfall in any one of them can gradually affect how you feel and function.

This reference covers the most nutritionally significant micronutrients, what each one does, and where to find it in food. For a complementary look at how macronutrients fit into the picture, see how protein, carbs, and fat work in your body.

Key Vitamins at a Glance

Vitamins are divided into two groups based on how the body stores and uses them:

• Fat-soluble vitamins (A, D, E, K) dissolve in fat and are stored in body tissues. Because they accumulate, excessive supplementation carries risk.
• Water-soluble vitamins (C and the eight B vitamins) dissolve in water, are not stored in large amounts, and need regular replenishment through food.

Fat-Soluble Vitamins

Vitamin A

Supports vision (especially in low light), immune function, and skin cell renewal. Found in liver, dairy, eggs, and as beta-carotene in orange and dark green vegetables.

Vitamin D

Regulates calcium absorption and bone mineralization; also plays a role in immune response. Synthesized by skin after sun exposure; dietary sources include fatty fish, fortified milk, and egg yolks.

Vitamin E

Acts as an antioxidant, protecting cells from oxidative damage. Concentrated in nuts, seeds, and vegetable oils.

Vitamin K

Essential for blood clotting and bone metabolism. Leafy greens — kale, spinach, broccoli — are the richest sources.

Water-Soluble Vitamins

Vitamin C

Supports collagen synthesis, immune defense, and iron absorption. Citrus fruits, bell peppers, strawberries, and broccoli are excellent sources.

B Vitamins (collective)

The eight B vitamins — including B1 (thiamine), B2 (riboflavin), B3 (niacin), B6, B9 (folate), and B12 — collectively support energy metabolism, nerve function, and red blood cell production. Whole grains, legumes, meat, fish, eggs, and dairy cover most of these. Folate is critical during early pregnancy; B12 is found almost exclusively in animal products, making it a key consideration for plant-based eaters. See what plant-based eaters need to plan for for more detail.

Key Minerals at a Glance

Minerals are split into macrominerals (needed in larger amounts, such as calcium and magnesium) and trace minerals (needed in tiny amounts, such as iron and zinc). Both are equally essential.

Calcium

The most abundant mineral in the body, critical for bone and tooth structure, muscle contraction, and nerve signaling. Dairy products, fortified plant milks, tofu made with calcium sulfate, and leafy greens are reliable sources.

Iron

Central to hemoglobin — the protein that carries oxygen in red blood cells. Comes in two forms: heme iron (meat, poultry, seafood — absorbed efficiently) and non-heme iron (legumes, fortified cereals, spinach — absorbed less efficiently but enhanced by pairing with vitamin C).

Magnesium

Involved in more than 300 enzymatic reactions, including energy production, protein synthesis, and blood glucose regulation. Found in nuts, seeds, whole grains, leafy greens, and legumes.

Potassium

Helps maintain fluid balance and supports healthy blood pressure. Bananas, potatoes, beans, and dairy are good sources.

Zinc

Supports immune function, wound healing, and DNA synthesis. Found in meat, shellfish, legumes, nuts, and seeds.

Iodine

Required for thyroid hormone production, which regulates metabolism. Iodized table salt and seafood are the primary sources in the American diet.

Understanding how these nutrients appear on food packaging can help you make more informed choices. Learn what the nutrition label is actually telling you, including how to read % Daily Values for key micronutrients.

Getting What You Need Through Food

For most healthy adults, a varied diet that includes vegetables, fruits, whole grains, legumes, protein sources, and dairy (or fortified alternatives) will cover the majority of micronutrient needs without supplementation. No single food supplies everything — dietary variety is the most practical strategy.

Certain groups may have increased needs or absorption challenges: older adults often absorb B12 and vitamin D less efficiently; people who are pregnant need more folate and iron; those following a fully plant-based diet should pay deliberate attention to B12, vitamin D, calcium, iron, zinc, and iodine. If you're building weekly meals with nutritional balance in mind, this practical starting point for meal planning can help structure your approach.

Supplements can fill specific gaps, but they are not a substitute for a nutritious diet and should be chosen based on individual need — ideally guided by a healthcare provider or registered dietitian. A periodic self-check on your eating patterns can be useful; this weekly nutrition self-check offers a practical, pressure-free way to do that.

This article is for general informational and educational purposes only and is not a substitute for professional medical or nutritional advice. Consult a qualified healthcare provider or registered dietitian for guidance tailored to your individual health needs.