You probably have that friend who swears by the vitamin regimen they take every morning. Maybe they've even bragged about their newfound energy, glowing skin, and super-strong immune system. There's a good chance you've wondered if you should hop on the vitamin bandwagon and pop a slew of supplements to start your day, too.
Well, it turns out there's no one-size-fits-all when it comes to vitamins. So, what vitamins do you actually need, and how do you know if you need them? We spoke with dietitians to get the scoop on the most important vitamins for your health, how to tell if you have a nutritional deficiency, and which vitamin supplements are worth adding to your routine.
The Essential Vitamins You Need (And Why)
There are 13 essential vitamins that your body requires to function at its best. These include vitamins A, C, D, E, K, and the B-complex vitamins (thiamine, riboflavin, niacin, pantothenic acid, biotin, B6, B12, and folate). Each of these plays a unique role in keeping your body running smoothly—from supporting your immune system to maintaining healthy skin, bones, and brain function. Vitamin D, for example, is crucial for bone health and immune function, while B vitamins are key players in energy metabolism and nerve function. The best way to get these nutrients? A balanced diet rich in fruits, vegetables, whole grains, lean proteins, and healthy fats. But for some people—like those with dietary restrictions, absorption issues, or specific health conditions—supplements can help fill in the gaps.
Who Really Needs Vitamin Supplements?
While most people can get the vitamins they need from food, certain groups are more likely to experience deficiencies and may benefit from supplementation. Vegetarians and vegans, for instance, often struggle to get enough vitamin B12, which is primarily found in animal products. Older adults may have trouble absorbing B12 due to decreased stomach acid production, and people with digestive disorders like celiac disease or Crohn’s disease may not absorb nutrients efficiently. Pregnant women need extra folic acid to prevent birth defects, and those living in northern climates with limited sunlight might need vitamin D supplements. If you fall into one of these categories, it’s worth talking to a healthcare provider about whether supplements could help.
Red Flags: Signs You Might Be Deficient
Nutrient deficiencies don’t always announce themselves with flashing neon signs, but there are some subtle (and not-so-subtle) clues your body might be sending. Fatigue, brittle nails, hair loss, muscle cramps, and frequent infections can all signal that something’s off. Vitamin B12 deficiency, for example, can cause numbness in your hands and feet, brain fog, and even mood changes. Low iron levels might leave you feeling exhausted and short of breath, while a lack of vitamin D can contribute to bone pain and a weakened immune system. If you’re experiencing persistent symptoms, a simple blood test can confirm whether you’re deficient—so don’t just guess and start popping pills without checking first.
The Dark Side of Over-Supplementing
More isn’t always better when it comes to vitamins. Some nutrients, like fat-soluble vitamins A, D, E, and K, can build up in your body and reach toxic levels if you take too much. Excessive vitamin A can lead to liver damage, while too much vitamin D can cause calcium buildup in your blood, leading to kidney stones or heart issues. Even water-soluble vitamins like vitamin C and B-complex can cause problems in mega-doses—think nausea, diarrhea, or nerve damage. That’s why it’s crucial to stick to recommended dosages and avoid doubling up on supplements unless a healthcare professional advises it. Remember, supplements should complement your diet, not replace real food.
How to Pick the Right Vitamin Brand
The supplement aisle can feel like a minefield of questionable claims and flashy packaging. To avoid wasting money (or worse, harming your health), look for third-party certifications like USP, NSF, or ConsumerLab, which verify that a product contains what it claims and isn’t contaminated with harmful substances. Opt for supplements with bioavailable forms of nutrients—like methylcobalamin for B12 instead of cyanocobalamin—since they’re easier for your body to absorb. And don’t assume that a higher dose equals better results—stick to the recommended daily allowance unless your doctor says otherwise. If you’re unsure where to start, a registered dietitian or pharmacist can help steer you toward trustworthy brands.
At the end of the day, vitamins are just one piece of the health puzzle. While they can help fill nutritional gaps, they’re not a magic bullet for poor eating habits or an unhealthy lifestyle. Focus on building a balanced diet first, and use supplements strategically—not as a crutch. And always, always check with a healthcare provider before starting any new regimen, especially if you’re pregnant, taking medications, or managing a chronic condition. Because when it comes to your health, knowledge is the best supplement of all.
