Supplement Guide

A naturally occurring compound found in meat and fish. Your body makes some, but supplementing tops up your stores. Creatine monohydrate is the gold standard form — no need for fancy versions.

Hundreds of peer-reviewed studies over 30+ years consistently show improvements in strength, power output, and lean muscle mass. Also shows promise for brain health and recovery from concussion. One of the very few supplements with genuinely strong evidence behind it.

3–5g daily. No need to load. Take it at any time — consistency matters more than timing.

~£10/month

Yes, for most people. Safe, cheap, and effective. One of the few supplements that genuinely delivers on its promises.

A protein derived from milk during cheese production. Available as concentrate (cheaper, ~80% protein) or isolate (more processed, ~90% protein, less lactose). It’s not a steroid. It’s not even a drug. It’s powdered milk protein.

Strong evidence that adequate protein intake (1.6–2.2g/kg bodyweight) supports muscle growth and recovery. Whey is simply a convenient, fast-absorbing source. It has no advantage over the same amount of protein from whole food — it’s just more practical.

20–40g per shake, as needed to hit your daily protein target.

~£20–30/month

Yes, if you struggle to hit your protein target from food alone. If you’re already eating enough protein, you don’t need it.

The world’s most popular psychoactive substance. Found in coffee, tea, and pre-workout supplements. Improves alertness, focus, and physical performance by blocking adenosine receptors in the brain.

Robust evidence for improved endurance, strength, and power output. Also improves focus and reduces perceived effort during training. One of the most well-researched ergogenic aids in sports science.

3–6mg per kg of bodyweight, taken 30–60 minutes before training. For an 80kg person, that’s roughly 240–480mg (2–4 cups of coffee).

Basically free if you drink coffee. Pre-workout supplements cost more but caffeine is the main active ingredient in most of them.

Yes. You’re probably already using it. Just be mindful of timing — avoid it within 8 hours of bedtime.

A fat-soluble vitamin your body produces when skin is exposed to sunlight. Essential for bone health, immune function, and mood regulation. In the UK, sunlight is insufficient for vitamin D production from roughly October to March.

The NHS recommends supplementation for everyone in the UK during autumn and winter. Deficiency is linked to weakened bones, impaired immune function, low mood, and poor recovery. Studies consistently show benefits of supplementation when levels are low.

1,000–2,000 IU (25–50μg) daily. Take with food containing fat for better absorption. Vitamin D3 is preferred over D2.

~£5/month

Yes, especially from October to March in the UK. Possibly year-round if you work indoors or have darker skin.

A source of EPA and DHA, two omega-3 fatty acids with anti-inflammatory properties. Found naturally in oily fish like salmon, mackerel, and sardines.

Moderate evidence for cardiovascular health benefits and reduced inflammation. May support joint health and recovery. The evidence is stronger if your diet is already low in omega-3 (i.e., you rarely eat fish). Less compelling if you already eat 2–3 portions of oily fish per week.

1–3g combined EPA and DHA daily. Look at the label — total fish oil and actual EPA+DHA content are different things.

~£10/month

Maybe, if you don’t eat fish regularly. If you eat oily fish 2–3 times a week, you probably don’t need it.

An essential mineral involved in over 300 enzymatic processes in the body, including muscle contraction, nerve function, and energy production. Many people are mildly deficient without realising it, especially those who train hard.

Some evidence that supplementation improves sleep quality, reduces muscle cramps, and supports recovery — particularly when dietary intake is insufficient. The form matters: magnesium glycinate or citrate are better absorbed than oxide.

200–400mg before bed. Magnesium glycinate is preferred for sleep; citrate for general use.

~£8/month

Worth trying if your sleep is poor or you experience frequent muscle cramps. Not essential if your diet is rich in nuts, seeds, and leafy greens.

A non-essential amino acid that increases carnosine levels in muscles. Carnosine acts as a pH buffer, potentially delaying the “burn” you feel during high-rep or endurance exercise.

Moderate evidence for improved performance in activities lasting 1–4 minutes (high-rep sets, interval training, rowing). Less relevant for low-rep strength work or long-duration cardio. The benefit is real but modest.

3–5g daily. Like creatine, it needs to accumulate over time — timing doesn’t matter.

~£10/month

Maybe, if you do a lot of high-rep or endurance-focused training. Probably not worth it for casual gym-goers or strength-focused athletes.

An ancient adaptogenic herb (Withania somnifera) used in traditional Ayurvedic medicine. Modern research has focused on its potential to lower cortisol, reduce stress, and improve recovery in athletes.

Some evidence for reduced cortisol levels, improved stress resilience, and modest improvements in strength and recovery. Most studies use KSM-66 or Sensoril branded extracts. The evidence is promising but still developing — not as strong as creatine or caffeine.

300–600mg of a standardised extract (KSM-66 or equivalent) daily.

~£12/month

Maybe, if you’re chronically stressed or overtrained. Address the root causes of stress first — no pill fixes a lifestyle problem.

Branched-chain amino acids (leucine, isoleucine, valine) — three of the essential amino acids. Heavily marketed as muscle-building and recovery supplements.

BCAAs are found in all complete protein sources. If you eat adequate protein (or use whey), you’re already getting more BCAAs than any supplement provides. Studies showing benefits of BCAAs were typically conducted in protein-deficient subjects. For anyone eating a normal diet, they offer no additional benefit.

N/A — you’re better off spending that money on food or whey protein.

~£15–25/month (for flavoured water, essentially)

No. One of the most overhyped supplements in the fitness industry. If you eat enough protein, BCAAs are redundant.

A category of supplements claiming to naturally boost testosterone levels. Usually contain ingredients like tribulus terrestris, fenugreek, D-aspartic acid, or zinc — often in proprietary blends with undisclosed doses.

No over-the-counter supplement has been shown to meaningfully increase testosterone in healthy men. Some ingredients may slightly increase testosterone in deficient individuals, but the effect is nowhere near what the marketing suggests. The proven ways to optimise testosterone are: sleep 7–9 hours, maintain a healthy body fat percentage, lift heavy weights, manage stress, and eat enough calories and micronutrients.

N/A — save your money.

~£25–50/month (for placebo)

No. These are the snake oil of the supplement industry. If you genuinely suspect low testosterone, see a doctor and get a blood test — don’t buy pills from Instagram ads.

Supplements claiming to increase metabolism, burn fat, or suppress appetite. Most are caffeine combined with various herbal extracts, green tea, and sometimes ingredients with little to no evidence behind them.

The “active ingredient” in most fat burners is caffeine, which does slightly increase metabolic rate — but you can get the same effect from a cup of coffee for pennies. No supplement meaningfully bypasses the need for a calorie deficit. Some products contain stimulants that can be harmful at high doses.

N/A — just drink coffee and fix your diet.

~£20–40/month (for expensive caffeine)

No. A calorie deficit is what burns fat. No pill replaces that. These products prey on people looking for shortcuts that don’t exist.

The most abundant amino acid in the body. Your body produces it naturally, and it’s found in most protein-rich foods. It plays a role in gut health and immune function.

Glutamine supplementation may benefit people who are critically ill, severely burned, or in extreme catabolic states. For healthy individuals who eat adequate protein, supplementation has shown no benefit for muscle growth, recovery, or performance. Your body already makes plenty.

N/A — unnecessary for healthy, adequately-fed individuals.

~£12–18/month (for something your body makes for free)

No. Another supplement that sounds sciencey but doesn’t deliver for the average gym-goer. Save your money.