What Supplements Should I Actually Be Taking?

Everyone wants to know which supplements they should take. Walk into any health store and you're faced with walls of bottles promising everything from better energy to clearer skin to a stronger immune system.

Here's the truth: there's no universal supplement stack that works for everyone. What your body needs depends on your diet, lifestyle, health conditions, medications, and even your genetics.

But there are patterns. Certain deficiencies are incredibly common, and certain symptoms point to specific nutritional gaps. Let's break down how to figure out what you actually need.

The Supplements Most People Are Deficient In

Before we get into specific recommendations, these are the nutrients that most people in modern society don't get enough of:

Vitamin D

Who's Deficient	Signs You Might Need It
Office workers	Fatigue, low mood
People in northern climates	Frequent illness
Those with darker skin	Muscle weakness
Elderly individuals	Bone pain
Anyone who avoids the sun	Brain fog

Testing: Ask for 25-hydroxyvitamin D. Optimal is 40-60 ng/mL, though many feel best at 50-80 ng/mL.

Dosing: Most people need 2,000-5,000 IU daily, but this varies wildly based on your levels, body weight, and sun exposure. Get tested first.

Magnesium

An estimated 50-80% of Americans don't get enough magnesium. Modern farming has depleted soil levels, and stress burns through magnesium rapidly.

Signs of deficiency:

• Muscle cramps or twitches
• Restless leg syndrome
• Poor sleep quality
• Anxiety or irritability
• Constipation
• Heart palpitations

Best forms: Magnesium glycinate (best for sleep/anxiety), magnesium citrate (good for constipation), magnesium threonate (crosses blood-brain barrier).

Dosing: 300-400mg elemental magnesium at bedtime.

Omega-3 Fatty Acids

Unless you're eating fatty fish 3-4 times per week, you're probably not getting enough EPA and DHA.

Benefit	Research Support
Reduces inflammation	Strong
Supports brain health	Strong
Heart health	Strong
Joint pain	Moderate
Mental health	Moderate

Dosing: 2-3g of combined EPA/DHA daily. Look for products that list the actual EPA and DHA amounts, not just "fish oil."

Mouth To Gut lets you log supplement additions one at a time and track how your symptoms shift over days and weeks — the only real way to know what's working.

Supplements Based on Your Symptoms

If You're Always Tired

Fatigue is one of the most common complaints, and it can stem from multiple deficiencies:

Check these first:

• Iron/Ferritin - Especially if you're a menstruating woman, vegetarian, or have heavy periods. Ferritin under 50 ng/mL often causes fatigue even if hemoglobin looks normal.
• B12 - Critical for energy production. Vegans and vegetarians are at high risk, as are people on acid-blocking medications.
• Vitamin D - Low D is strongly linked to fatigue and low mood.
• Thyroid function - Not a supplement issue, but rule this out.

Consider adding:

• CoQ10 (100-200mg) - Especially if you're over 40 or on statins
• B-Complex - If your diet is poor or you're under chronic stress

If You Have Brain Fog

That fuzzy, can't-concentrate feeling often points to:

• Omega-3s - Your brain is 60% fat and needs DHA
• B12 - Essential for nerve function and mental clarity
• Magnesium - Involved in hundreds of brain processes
• Vitamin D - Low levels linked to cognitive issues
• Iron - Your brain needs oxygen, and iron carries it there

Nootropic additions to consider:

• Phosphatidylserine (300mg) - Supports memory and focus
• Lion's Mane mushroom - Supports nerve growth factor

If You Have Gut Issues

Digestive problems often respond well to targeted supplementation:

Issue	Consider
Bloating after meals	Digestive enzymes
Irregular bowels	Magnesium citrate, fiber
Suspected leaky gut	L-Glutamine (5-10g daily)
After antibiotics	High-quality probiotic
Acid reflux	Zinc carnosine, DGL licorice

If You Have Inflammation or Joint Pain

Chronic inflammation underlies most modern diseases. These supplements have anti-inflammatory effects:

• Omega-3s - The foundation of any anti-inflammatory protocol
• Curcumin - Take with black pepper (piperine) for absorption
• Magnesium - Low magnesium increases inflammatory markers
• Vitamin D - Regulates immune function and inflammation
• Ginger - Particularly good for joint pain

How to Know If Supplements Are Working

This is where most people go wrong. They start taking supplements and never track whether they're actually helping.

What to track:

• Energy levels (1-10 scale, multiple times per day)
• Sleep quality
• Specific symptoms you're trying to address
• Any new symptoms (could indicate you're taking too much)

Give it time: Most supplements need 2-4 weeks to show effects. Some, like vitamin D, can take 2-3 months to fully optimize your levels.

Retest: If you started supplementing based on blood work, retest after 3 months to see if levels have improved.

The Supplements to Be Careful With

Not all supplements are "more is better." These can cause problems if overdone:

Supplement	Risk of Excess
Iron	Toxic in excess - only take if deficient
Vitamin A	Can cause liver damage and birth defects
Vitamin B6	Nerve damage at high doses (over 100mg)
Zinc	Can deplete copper if taken long-term
Vitamin E	May increase bleeding risk
Selenium	Narrow therapeutic window

Rule: If it's a mineral or fat-soluble vitamin, get tested before taking high doses long-term.

A Sensible Starting Stack

If you're not sure where to start and can't get testing done immediately, these are generally safe and address common deficiencies:

1. Vitamin D3 + K2 - 2,000-4,000 IU D3 with 100mcg K2
2. Magnesium Glycinate - 300-400mg at bedtime
3. Omega-3 Fish Oil - 2g EPA/DHA daily
4. B-Complex - If your diet isn't great

Add these one at a time, a week apart, so you can notice if any cause issues.

The Real Answer: It Depends on You

Generic supplement advice can only take you so far. What you actually need depends on:

• What you eat (and don't eat)
• Your symptoms and health patterns
• Your current health conditions
• Medications you take
• Your genetics
• Your stress levels and lifestyle

This is why tracking matters. When you log your food, symptoms, energy levels, and supplements daily, patterns emerge. You start to see that your energy crashes when you skip your magnesium, or that your joint pain improved two weeks after starting omega-3s.

Related Reading

• Iron Deficiency Signs You're Ignoring
• Why Am I So Tired After 8 Hours of Sleep?
• The Gut-Brain Connection
• Anti-Inflammatory Diet Basics

Track This With Mouth To Gut

Add one supplement to your routine and track your symptoms and energy over the next 2-3 weeks. Mouth To Gut shows you which additions actually move the needle on how you feel. Start tracking free →