From Multivitamins to Omega-3s: Which Supplements Do Adults Really Need?

The supplement aisle at your local U.S. grocery store can feel like a maze—rows of bottles promising better energy, stronger immunity, or sharper focus. With so many options, it’s easy to wonder: Which supplements are actually worth adding to your routine? Let’s cut through the noise and break down what adults really need, based on science and lifestyle.

1. Multivitamins: A Safety Net (But Not a Replacement)

Multivitamins are the most popular supplement in America, and for good reason—they’re a convenient way to fill nutrient gaps. If your diet is hit-or-miss (think busy workweeks with takeout), a daily multivitamin can cover basics like vitamins A, C, D, and B12.

But here’s the catch: They’re not a substitute for whole foods. A multivitamin won’t replace the fiber, antioxidants, or phytochemicals in a spinach salad or grilled salmon.

2. Omega-3s: Critical for Heart and Brain

If you don’t eat fatty fish (salmon, mackerel, sardines) at least twice a week, an omega-3 supplement (like fish oil or algae-based for vegetarians) is a smart move.

Omega-3s support heart health by lowering triglycerides, reduce inflammation, and may even boost brain function—important for adults of all ages, especially as we get older.

3. Vitamin D: The "Sunshine Vitamin" Many Lack

Most Americans don’t get enough vitamin D. Why? We spend less time outdoors, use sunscreen (which blocks D production), and winter months mean weaker sunlight in northern states.

Vitamin D is key for bone health (it helps absorb calcium) and immunity. Ask your doctor for a blood test—if levels are low, a supplement (1000–2000 IU daily) is usually recommended.

4. Probiotics: For Gut Health (If You Need Them)

Your gut microbiome affects everything from digestion to mood, but do you need a probiotic? It depends.

They’re helpful if you’ve taken antibiotics (which kill good bacteria) or have IBS. Look for strains like Lactobacillus or Bifidobacterium, and pair them with prebiotic foods (garlic, onions, oats) to feed the good bacteria.

5. Protein Powders: A Boost for Specific Lifestyles

Protein powder (whey, plant-based, or collagen) isn’t necessary for most adults—you can get enough from chicken, eggs, beans, or Greek yogurt.

But it’s handy if you’re a gym regular (aiming for 1.2–2.0g of protein per kg of body weight), older adults (to preserve muscle), or struggle to eat enough protein due to busy schedules.

The Bottom Line: Less Is Often More

Focus on whole foods first, then add supplements to fill specific gaps. For most adults, a multivitamin (if your diet is inconsistent), omega-3s (if you skip fish), and vitamin D (if you’re low) are the big three. Always check with your doctor before starting a new supplement—especially if you take medication.