Top 5 Supplements That Actually Work (Based on Science)

So you’ve wandered into a supplement shop (or scrolled through TikTok for more than 7 seconds) and now you're convinced you need 19 powders, 7 pills, and a magic metabolism tea to lose fat and feel better.

Let’s slow that train right down.

Most of the supplement industry is smoke, mirrors, and overpriced caffeine. But there are a few key ones worth taking — and no, they’re not flashy. They’re just backed by actual research.

This post breaks down the only 5 supplements most people actually need — especially if you're 35+, trying to lose fat, build strength, or just stop wasting money.

Let’s get into it.

1. Creatine Monohydrate

What it is: A naturally occurring compound that helps your muscles make energy during high-intensity exercise.

Why it matters:

• It helps you lift heavier, train harder, and recover faster

• It supports muscle growth — critical as you age

• It's safe. Creatine doesn't ruin kidneys unless you already have serious kidney issues. Stop listening to Karen from Facebook.

  
  

How to take it: 5g daily. Anytime. No need to load. No need to cycle.

Who should take it: You. Me. Your dad. Your clients. Anyone who trains and wants to keep or build muscle. Especially as you hit 35 and up.

2. Whey Protein

What it is: A convenient, high-quality protein source made from milk.

Why it matters:

• Hitting your protein goal is non-negotiable if you want to lose fat or build lean mass

• Protein shakes aren’t magic — they’re just a useful backup when your food falls short

  
  

How to take it: Blend it. Shake it. Stir it into porridge. Use it when you’re in a rush or short on protein.

Who should take it: Anyone not hitting around 1.6–2.2g of protein per kg of bodyweight through real meals. (Which is… most people.)

3. Vitamin D3

What it is: A vitamin your body makes from sunlight — but not if you live in the UK and the sky’s been grey for 8 straight months.

Why it matters:

• Supports immunity, mood, energy, and hormone function

• Most adults in the UK are deficient, especially in winter

  
  

How to take it: 2,000–4,000 IU per day with food. Easy.

Who should take it: Anyone who doesn’t get daily sun exposure or hasn’t had their levels tested. (So... most of us.)

4. Omega-3 (Fish Oil or Algae-Based)

What it is: Essential fats your body needs but can’t make on its own.

Why it matters:

• Supports heart, brain, and joint health

• Helps reduce inflammation

• You’re not eating enough oily fish — don’t lie

  
  

How to take it: 250–500mg EPA/DHA per day. Look at the label — don’t just trust the front of the bottle.

Who should take it: Anyone not eating salmon, sardines, or mackerel 2–3 times a week. (Be honest.)

5. Magnesium (Citrate or Glycinate)

What it is: A mineral involved in over 300 functions in your body, from muscle function to sleep to stress regulation.

Why it matters:

• Helps with sleep quality and recovery

• Supports mood, relaxation, and performance

• Many adults are low, especially active ones

How to take it: 200–400mg before bed. Avoid magnesium oxide — it’s cheap and doesn’t absorb well.

Who should take it: Anyone training hard, sleeping poorly, or feeling wired and tired.

But What About Fat Burners? BCAAs? Detox Teas?

Nah.

Fat burners: Usually just caffeine. Won’t burn fat unless you’re in a calorie deficit. Save your money.

BCAAs: Pointless if you eat enough protein. If you don’t — fix that first.

Detox teas: Your liver and kidneys detox your body daily. These are just expensive laxatives with fancy branding.

Bottom Line:

You don’t need a supplement stack that looks like a bodybuilder’s bathroom shelf.

Stick to the basics. Nail your nutrition, training, steps, and sleep. Then — if you still need support — consider:

✅ Creatine✅ Whey protein✅ Vitamin D3✅ Omega-3✅ Magnesium

That’s it.

This is exactly how we do it inside RSG Coaching. Just stuff that works.

Want help building a results-based routine without all the confusion?

Drop me a message. Let's get you sorted properly.