Fitness supplements: which ones are worth it and which are not
Supplements are optional: diet, training and sleep come first. Here is how to pick the few with real evidence behind them, and who each one actually suits.
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Our picks
IllustrativeCreatine monohydrate
Great value for money. Creatine monohydrate is the most studied supplement in the fitness world: it improves performance in short, explosive efforts and helps with hypertrophy in the long term. Standard dose is 3-5 g/day, no loading phase needed.
- Pure monohydrate, the most studied form
- 3–5 g a day, no loading phase needed
- Very low cost per serving
Best for: Build muscle · Hyrox
IllustrativeOptimum Nutrition Gold Standard 100% Whey 2.28 kg
Helps you reach your daily protein target without a high cost per gram. The most studied supplement and the best value for money.
Best for: Build muscle · Lose fat
IllustrativeMagnesium citrate
Very useful for preventing cramps and supporting recovery.
- Format
- Price
- Ease of use
Best for: General health · Running
IllustrativeESN Micellar Casein 1 kg
Slow-digesting micellar casein, handy as a night-time protein or between long gaps. For people who already hit their daily protein and want to spread it better.
- Slow digestion, keeps you fuller
- Thick mousse-like texture
- Known brand with several flavours
- No advantage if you already reach your daily protein
Best for: Build muscle
IllustrativeESN Ultrapure Creatine Monohydrate 500 g (Creapure)
Creatine monohydrate made from Creapure, the most studied form for gaining strength and muscle. For anyone who wants a verified-purity creatine at 3-5 g per day.
- Creapure, tested purity
- Microfine powder that dissolves well
- One tub gives about 140 servings
- Unflavoured, slightly noticeable in plain water
Best for: Build muscle · Train at home · Hyrox
IllustrativeHigh5 Zero sugar-free electrolyte tablets (20 count)
Effervescent tablets with sodium, potassium and magnesium and zero sugar, to replace salts in long sessions or heavy sweating. For runners and workouts over an hour.
- Zero sugar and almost no calories
- Easy to carry in a pocket
- With vitamin C
- Moderate sodium for very heavy sweaters
Best for: Running · Hyrox · General health
IllustrativeMultivitamin gummies
Multivitamins are very useful when you're in a calorie deficit, helping you get all your daily micronutrients.
- Complete
- Taste
- Ease of use
Best for: General health · Lose fat
IllustrativeMyprotein Impact Whey Isolate 1 kg
Whey isolate with very little fat and lactose and about 23-25 g of protein per serving. For people who tolerate concentrate poorly or want to control calories while cutting.
- High protein per serving
- Low in fat, sugar and lactose
- Many flavours and mixes well
- Costs more per gram than concentrate
Best for: Build muscle · Lose fat
IllustrativeNutravita Omega 3 2000 mg (240 capsules)
If your diet doesn't include oily fish 2-3 times a week, an omega-3 supplement helps cover the recommended intake of EPA and DHA. Triglyceride form for better absorption.
- Supports cardiovascular health
- Useful if you don't eat oily fish
Best for: General health
IllustrativeMyprotein shaker 600 ml
Mixing cup with a mesh or ball to dissolve whey without clumps. 600 ml leaves room to shake with water and/or milk without spilling. Essential if you use protein powder.
Best for: Build muscle
Illustrativenatural elements Vitamin D3 + K2 drops 50 ml
Vitamin D3 with K2 (all-trans MK-7) in drops, a practical option if you get little sun or have low blood levels. Easy to dose; check the amount with your doctor.
- D3 and K2 in one product
- Easy-to-dose drops
- One bottle lasts many months
- Confirm the dose with a blood test or your doctor
Best for: General health · Build muscle
Illustrativenutri+ neutral pea and rice protein 1 kg
Pea and rice protein blend, free from soy and lactose, with a complete amino acid profile. For vegan or lactose-intolerant people who need to reach their daily protein.
- Pea and rice complement each other's amino acids
- No soy, lactose or sweeteners
- Versatile: shakes, oats, baking
- Neutral taste and a slightly grainy texture
Best for: Build muscle · General health
Illustrativevit4ever caffeine tablets 200 mg (500 count)
Anhydrous caffeine in 200 mg tablets to dose 3-6 mg/kg precisely before training or racing. Handy if you dislike coffee or want an exact dose.
- Exact 200 mg per tablet
- Very cheap per dose
- No sugar or calories
- Avoid in the afternoon or evening: it affects sleep
Best for: Running · Hyrox · Build muscle
Quick comparison
| Product | Type | Budget | Best for |
|---|---|---|---|
| Creatine monohydrate | Best value | $ | Build muscle, Hyrox |
| Optimum Nutrition Gold Standard 100% Whey 2.28 kg | Best value | $$ | Build muscle, Lose fat |
| Magnesium citrate | Recommended | $ | General health, Running |
| ESN Micellar Casein 1 kg | Recommended | $$ | Build muscle |
| ESN Ultrapure Creatine Monohydrate 500 g (Creapure) | Recommended | $$ | Build muscle, Train at home, Hyrox |
| High5 Zero sugar-free electrolyte tablets (20 count) | Recommended | $ | Running, Hyrox, General health |
| Multivitamin gummies | Recommended | $ | General health, Lose fat |
| Myprotein Impact Whey Isolate 1 kg | Recommended | $$ | Build muscle, Lose fat |
| Nutravita Omega 3 2000 mg (240 capsules) | Recommended | $ | General health |
| Myprotein shaker 600 ml | Best value | $ | Build muscle |
| natural elements Vitamin D3 + K2 drops 50 ml | Best value | $ | General health, Build muscle |
| nutri+ neutral pea and rice protein 1 kg | Best value | $$ | Build muscle, General health |
| vit4ever caffeine tablets 200 mg (500 count) | Best value | $ | Running, Hyrox, Build muscle |
How to choose: food first, supplements second
A supplement should fill a specific gap, not replace meals. Before buying anything, work out your protein and calorie needs and check whether your usual diet already covers them. If it does, you may need very little.
Of everything on this page, only creatine monohydrate and protein powder have strong evidence and a clear role in training. The rest (omega-3, magnesium, multivitamin, electrolytes) are situational: they help when there is a shortfall or a specific need, and not much more.
- Start with one product and make sure you use it consistently before adding another.
- Prefer simple ingredient lists: plain creatine monohydrate, whey with a clear label.
- Look for third-party testing (such as Informed Sport) if you compete in a drug-tested sport.
What actually matters (and what doesn't)
What matters is the dose per serving, the form of the compound and taking it regularly. Creatine works at 3-5 g a day, taken consistently; you do not need a loading phase or an exotic brand. With whey, check grams of protein per serving and the ingredient list, not the flavor or the marketing.
Exact timing matters less than people think: taking protein or creatine right after training is not required, because the daily total is what counts. You also do not need formulas with dozens of ingredients, or fat-burner promises.
- Omega-3: makes sense if you rarely eat oily fish; check the mg of EPA and DHA, not just total oil.
- Magnesium: evidence for preventing cramps is limited; useful if your intake is low, not a universal fix.
- Multivitamin: modest insurance, mostly useful during a long calorie deficit or a restrictive diet.
Which option fits you
If you lift and want just one purchase, budget creatine monohydrate is the best value. If you struggle to hit your protein target from food, mid-range whey is convenient, and a basic shaker is all you need to mix it.
If you eat little fish, a triglyceride-form omega-3 is reasonable. If you do sessions longer than 60-90 minutes, train in the heat or sweat heavily, a sugar-free electrolyte mix can help; for ordinary workouts, water and food are enough. Magnesium and a multivitamin are low-cost options for specific cases, not essentials.
Safety and responsible use
Being sold as a supplement does not make something safe for everyone. Talk to a healthcare professional if you are pregnant, have kidney or liver problems, take medication or have a chronic condition. Stay within the label dose and buy from reputable sellers.
Frequently asked questions
Do I need supplements to build muscle?+
No. Muscle comes from progressive training, enough protein, adequate calories and sleep. Creatine adds a small but consistent benefit, and whey is simply a convenient way to reach your daily protein.
How much creatine should I take, and do I need to load?+
The usual dose is 3-5 g of monohydrate daily. Loading is not necessary; it only saturates your muscles a few days sooner. Take it consistently at whatever time of day suits you.
Is whey better than protein from food?+
No, it provides comparable amino acids and is just practical and easy to measure. If you already reach your target with whole foods, you do not need shakes.
Should I use electrolytes at every workout?+
No. They make sense for sessions over 60-90 minutes, in hot conditions or with heavy sweating. For a normal strength session, water and a meal with some salt are usually enough.