Compare energy and focus supplements on what's actually in them, which for most products in this collection means caffeine: the amount per serving, any other caffeine sources such as guarana, and the cost per serving. "Energy" and "focus" are what people search for, not promises; caffeine has no authorised health claims, so we show you the label facts and the safety figures instead.
All pre-workout · Energy drinks · Pre-workout shots · Moderate-stim pre-workout · Stim-free pre-workout · Nootropics
Filters
Clear all
What are energy and focus supplements?
It's a shopping category, not a type of ingredient. In this collection it covers caffeinated pre-workouts, pre-workout and energy shots, energy drinks, amino acid drinks with added caffeine, and guarana and herbal products.
What most of them have in common is caffeine. The International Society of Sports Nutrition (ISSN) review of energy drinks and shots found that the main active nutrients in most of these products appear to be caffeine and/or carbohydrate, and that the added value of the other ingredients remains to be determined.
Do energy supplements work?
We can't say they will give you more energy, and the law doesn't let anyone say that about caffeine: there is no authorised health claim for caffeine in the GB register of permitted health claims. What we can say is what's in each product and what the research has looked at.
The ISSN caffeine position stand reviews caffeine's effects on exercise and on mental tasks, and notes substantial differences in how individuals respond to caffeine. "Where evidence is limited or inconclusive, we should say so openly," says Andy Arshad, who runs SupplementHQ.
Are there authorised claims about tiredness and fatigue?
Yes, but for certain vitamins and minerals, not for caffeine. For example, "Iron contributes to the reduction of tiredness and fatigue" and "Magnesium contributes to a reduction of tiredness and fatigue" are authorised claims, and may be used only for food that is at least a source of iron or magnesium.
So a product can only make that claim if it contains enough of the vitamin or mineral, and the claim is about that nutrient, not the product's caffeine. If you're tired for a few weeks without knowing why, the NHS says to see a GP; it lists poor sleep, lifestyle, stress and some illnesses among the common causes.
How much caffeine is in energy supplements?
It ranges from none to a lot, so check the label on every product. A food supplement with added caffeine must carry the warning "Contains caffeine. Not recommended for children or pregnant women" and state the caffeine per daily portion.
| Source | Caffeine |
|---|---|
| Cup of tea | 75mg |
| 250ml can of energy drink | 80mg |
| Cup of instant coffee | 100mg |
| Caffeinated supplement | Check the label: varies by product |
The tea, coffee and energy drink figures are from the NHS. Guarana counts too: the UK government lists guarana and certain tea leaves as natural sources of caffeine, so a product made with guarana extract contains caffeine even if "caffeine" isn't in its name.
How much caffeine is safe a day?
EFSA (the European Food Safety Authority) says up to 400mg a day spread through the day, and single doses up to 200mg, do not raise safety concerns for healthy adults, apart from pregnant women. The NHS says pregnant women should have no more than 200mg a day.
The UK government advises avoiding supplements with more than 200mg of caffeine in a single serving, and adding up caffeine from all products, including tea, coffee, chocolate and energy drinks. It warns that high levels can cause anxiety, sleeplessness, agitation, palpitations, diarrhoea and restlessness.
Can you take energy supplements in the afternoon?
You can, but caffeine later in the day may affect your sleep: EFSA says 100mg may affect sleep in some adults, particularly close to bedtime. Check the caffeine per serving against that figure.
If you'd rather avoid caffeine, see our stim-free pre-workouts.
What about focus supplements?
"Focus" here is a search term. Most focus-labelled products in this collection rely on caffeine, and we don't claim any of them improve concentration. The ISSN position stand notes that studies reporting better vigilance and reaction time in sleep-deprived people used doses of about 200mg, and that effects were less clear in people who were not sleep-deprived.
"Adding more ingredients doesn't automatically make a product more effective. Each ingredient needs a clear purpose, an appropriate dose and evidence supporting its intended use," says Andy. Products sold for focus without caffeine are in our nootropics collection.
How do you compare value on energy supplements?
Compare the cost per serving and the caffeine per serving together, because a cheaper serving with less caffeine isn't like-for-like.
How to compare value (example figures, not real products): a £20 tub with 40 servings of 100mg caffeine costs 50p a serving, or 50p per 100mg. A box of 12 shots at £24 with 200mg each costs £2 a shot, or £1 per 100mg. The shots cost twice as much for the same caffeine. Check the full-strength serving size on every label, and compare more formats in our pre-workout guide.
We sell the products on this page. That's our commercial interest, and it's why we show the evidence alongside them. This page is general information for adults, not personalised medical advice. Food supplements should not replace a varied, balanced diet.
Written by Andy Arshad, SupplementHQ. Last reviewed 11 October 2026.