Most of the supplement shelf isn't doing anything

Go and look in the cupboard above your kettle. If you're anything like most men who lift a couple of times a week around a job and a school run, there are six or seven tubs in there, four of them open, two of them older than your youngest child. One of them is doing something. It probably cost the least.

That one is creatine monohydrate. Five grams a day, every day, no loading phase, timing irrelevant. It's the most studied sports supplement there is and the cheapest thing on the shelf by a wide margin. If you buy nothing else, buy that, and buy the plain unflavoured powder rather than the version with a logo and a flavour and four times the price per serving.

Now for the rest of the cupboard.

The test boosters

This is the category sold hardest to men over thirty-five and supported least by anything you'd want to rely on. Tribulus, D-aspartic acid, "hormone support" blends with a black-and-red label and a silhouette of a man on the front.

The marketing is clever because the symptoms it names are real. You are tired. You have less drive than you did at twenty-five. You do wake up at three in the morning thinking about work. All true. None of it is fixed by a capsule of powdered thistle.

If you genuinely think your testosterone is low, that's a blood test and a conversation with your GP, not a tub. Low testosterone is a medical diagnosis with medical treatment, and the thing that sells you the tub has every reason to keep you from finding out you don't need it. Meanwhile the three things that actually move the needle for most men in their forties are sleep, bodyweight and resistance training, and none of them have a marketing budget.

BCAAs, if you eat food

Branched-chain amino acids made sense in an era when people trained fasted and drank them during a session. If you're eating anything like enough protein across the day, you're already getting them, in better ratios, attached to a complete protein.

The tub of sour-apple BCAA in your gym bag is flavoured water. If you enjoy drinking it and it gets you through a session, fine, it isn't hurting you. But don't count it as part of your supplement budget. Count it as squash.

Pre-workout, and the proprietary blend trick

Turn the tub around and read the label. If the ingredients are grouped under something like "Focus Matrix 6,400mg" with a list underneath and no individual doses, you don't know what you're taking. That's the point. The expensive, exotic-sounding ingredients go in at a few milligrams so they can appear on the label, and the bulk of the weight is caffeine and cheap filler.

The industry term for this is fairy dusting, and once you've seen it you can't unsee it. A pre-workout that discloses every dose on the front is telling you something. One that hides them is also telling you something.

What's actually working in most pre-workouts is caffeine, at around 200 to 300mg. You can get that from two coffees. What's arguably working is citrulline and beta-alanine, and both need real doses to do anything, which most blends don't provide. The tingling in your face is the beta-alanine. It's harmless and it isn't a sign of potency.

Here's the trade-off, and it's a genuine one. If you train at 5am before a shift, or at nine at night after bedtime, a stimulant is sometimes the difference between doing the session and going back to bed. That has value. Just know that you're buying caffeine with a light show, and that caffeine takes around five hours for half of it to clear. A 7pm pre-workout is a 1am problem.

Greens powders

The pitch is that you're not eating vegetables and this fixes it. It doesn't. It's a dried, processed, expensive fraction of what vegetables do, missing most of the fibre and most of the volume, and the ingredient list is usually another proprietary blend.

I'll concede the honest version of the case. If you're travelling for work, eating from petrol stations, and the alternative is genuinely nothing, a scoop of something green isn't worse than nothing. But it's a plaster, and it costs more per month than a weekly bag of frozen spinach and a box of satsumas.

Fat burners

Almost always caffeine plus an appetite suppressant plus something that makes you sweat, sold at a markup that only works because the customer is unhappy with how he looks and in a hurry. The weight that comes off comes off because you ate less, and you ate less because you were caffeinated and jittery. Which is not a plan you can run for five years while raising children.

Some of these have been pulled from sale over the years for containing things that shouldn't have been in them. The supplement industry isn't regulated like medicine. If you take any prescription medication, particularly for blood pressure, heart rhythm or blood thinning, ask a pharmacist before you add anything stimulant-based. That conversation is free and takes four minutes.

What survives the audit

Short list.

• Creatine monohydrate. 3 to 5g daily. Cheap, well evidenced, no timing rules.
• Protein powder. Not magic. It's a convenient food when you're short on protein and short on time, which as a working parent you frequently are. Whey, plain, buy the big bag.
• Caffeine. Coffee is fine. Know your cut-off time.
• Vitamin D, if you live somewhere with a British winter and work indoors. Dose is worth asking your GP or pharmacist about rather than guessing from a forum.

That's it. Everything else in your cupboard is optional at best, and most of it is the supplement industry selling you the feeling of taking training seriously.

How to tell what's worth it, in thirty seconds

Pick up the tub and run these:

• Are individual doses listed for every active ingredient? No means put it down.
• Is the dose in line with what's actually been studied for that ingredient, or is it a tenth of it?
• Does the label make a claim about a hormone, a body part or a feeling, rather than about a nutrient?
• Is there a third-party testing mark like Informed Sport or NSF Certified for Sport? If you're in the military, in a tested job, or competing in anything, this matters more than the ingredient list.

The last one catches a lot of people out. Contamination in this industry isn't theoretical, and "I didn't know it was in there" has never once worked as a defence.

The uncomfortable part

Most of us buy supplements at the exact moment we're least likely to train consistently. New job, new baby, thirty-nine birthday, whatever it is. The purchase is a substitute for the habit, and it feels productive because money left your account.

Six weeks later the tub is still three-quarters full and the training didn't happen. Then the next tub gets blamed for not working.

If your sleep is six hours and your protein is 70g and you're training once a fortnight, there is no powder on earth that makes a difference worth measuring. Fix the boring things first. They're free, they're slower, and they're the only ones that still work in five years.

Finish the tubs you've got. Then buy one thing, not eight, and let it be the cheap one.

General information only. For anything involving your own health, medication or blood work, talk to your GP or a pharmacist.