The supplements most commonly associated with normal energy levels include vitamin B complex, vitamin B12, magnesium, vitamin C and iron. However, no supplement can guarantee an instant energy boost, and the right choice depends on your diet, lifestyle and whether you have a nutritional deficiency.
Several vitamins and minerals contribute to normal energy-yielding metabolism or the reduction of tiredness and fatigue. This does not mean that taking more than you need will produce additional energy.
Persistent or unexplained tiredness should be discussed with a GP, particularly when it affects everyday life or occurs alongside other symptoms.
Why do people feel tired?
Feeling tired occasionally is normal, especially following a busy period, disrupted sleep or increased physical activity.
Common reasons for tiredness can include:
- Not getting enough sleep
- Stress or low mood
- An unbalanced diet
- Not eating regularly
- Dehydration
- Limited physical activity
- Hormonal changes
- Caring responsibilities
- Working long or irregular hours
- Recovering from an illness
Tiredness can also be associated with medical conditions or nutrient deficiencies. NHS guidance advises seeking medical advice when tiredness has continued for several weeks, affects daily life or is accompanied by other unexplained symptoms.
Can supplements improve energy levels?
A supplement may be useful when your diet does not provide enough of a particular nutrient or when a healthcare professional has identified a deficiency.
However, supplements do not provide energy in the same way as food. Calories from carbohydrates, fats and protein provide the body with energy, while vitamins and minerals support the processes that help the body release and use that energy.
Taking extra vitamins will not necessarily make someone feel more energetic when they already have an adequate intake.
For example, NHS guidance states that vitamin B12 treatment may improve tiredness when low vitamin B12 is the cause. It is not expected to improve tiredness caused by an unrelated issue.
Which nutrients contribute to normal energy?
The Great Britain Nutrition and Health Claims Register contains authorised claims for nutrients used in food supplements.
Depending on the nutrient, these can include contributions to:
- Normal energy-yielding metabolism
- The reduction of tiredness and fatigue
- Normal functioning of the nervous system
- Normal psychological function
- Normal red blood cell formation
- Normal oxygen transport in the body
Only authorised claims may be used commercially in Great Britain, and the product must contain enough of the relevant nutrient to meet the conditions of use. The register was most recently updated in May 2026.
1. Vitamin B complex
A vitamin B complex usually combines several or all of the eight recognised B vitamins:
- Vitamin B1, or thiamine
- Vitamin B2, or riboflavin
- Vitamin B3, or niacin
- Vitamin B5, or pantothenic acid
- Vitamin B6
- Vitamin B7, or biotin
- Vitamin B9, or folate
- Vitamin B12
Different B vitamins perform different functions, but several contribute to normal energy-yielding metabolism. Some, including vitamins B6 and B12, also contribute to the reduction of tiredness and fatigue when the product meets the conditions for those claims.
A vitamin B complex may suit people who:
- Want several B vitamins in one daily product
- Prefer an all-in-one formula rather than separate bottles
- Follow a restricted or inconsistent diet
- Want to compare their intake of several B vitamins
- Are looking for nutritional support for an active routine
What to check
Look at the amount of each B vitamin rather than relying only on phrases such as “high strength”.
Some products provide very large amounts compared with the nutrient reference value. A larger number does not automatically mean a better product.
The NHS advises not taking more than 10mg of vitamin B6 per day from supplements unless advised by a doctor. Check other products you use because multivitamins, magnesium complexes and sports supplements may also contain vitamin B6.
2. Vitamin B12
Vitamin B12 contributes to normal energy-yielding metabolism, normal red blood cell formation and the reduction of tiredness and fatigue.
It is naturally found in animal-derived foods, including:
- Meat
- Fish
- Eggs
- Milk
- Cheese
- Some fortified foods
People following a vegan diet need a reliable source of vitamin B12 through fortified foods or supplements because it is not naturally present in most plant foods.
Vitamin B12 may be relevant for people who:
- Follow a vegan or highly restricted diet
- Have previously been advised that their intake is low
- Use a supplement recommended by a healthcare professional
- Prefer a standalone B12 product rather than a complete B complex
Vitamin B12 supplements are available as tablets, capsules, sprays and liquid drops. The best format is usually the one that provides a clearly labelled amount and is easy to use consistently.
Important point
Extreme tiredness, lack of energy, pins and needles, muscle weakness and memory problems can occur with vitamin B12 or folate deficiency. These symptoms should not be self-diagnosed because they can have many causes.
3. Magnesium
Magnesium is a mineral that contributes to:
- Normal energy-yielding metabolism
- A reduction in tiredness and fatigue
- Normal muscle function
- Normal functioning of the nervous system
- Normal psychological function
- Electrolyte balance
Magnesium is found naturally in foods such as nuts, seeds, leafy green vegetables, beans and whole grains.
Magnesium may suit people who:
- Want a mineral that supports several normal bodily functions
- Prefer a supplement for both energy metabolism and muscle function
- Are comparing single-form and multi-form magnesium products
- Want magnesium as part of a daily wellness routine
Magnesium is available in forms including glycinate, citrate, oxide, malate and multi-form complexes.
The type of magnesium, elemental amount, serving size and digestive tolerance all matter. A product listing a large amount of a magnesium compound may provide a much smaller quantity of actual elemental magnesium.
4. Vitamin C
Vitamin C contributes to:
- Normal energy-yielding metabolism
- A reduction in tiredness and fatigue
- Normal functioning of the immune system
- Protection of cells from oxidative stress
- Normal collagen formation
It also increases iron absorption.
Vitamin C is naturally found in:
- Oranges and other citrus fruits
- Peppers
- Strawberries
- Blackcurrants
- Broccoli
- Potatoes
Vitamin C may suit people who:
- Have a limited intake of fruit and vegetables
- Want a standalone vitamin C supplement
- Prefer vitamin C as part of a multivitamin
- Have been advised to consider vitamin C alongside dietary iron
Vitamin C supplements are available as capsules, tablets, gummies, powders and liquid products.
A high-strength product is not automatically necessary. Check the amount per serving, number of servings and any additional ingredients.
5. Iron
Iron contributes to:
- Normal energy-yielding metabolism
- The reduction of tiredness and fatigue
- Normal formation of red blood cells and haemoglobin
- Normal oxygen transport in the body
Iron deficiency anaemia can cause tiredness, a lack of energy, shortness of breath, headaches and noticeable heartbeats. However, these symptoms can also have other causes and should be properly assessed.
Iron is different from a general energy supplement
Iron should not be taken simply as a routine “pick-me-up” without considering whether it is needed.
Too much iron can be harmful, and iron supplements can cause:
- Constipation
- Nausea
- Stomach pain
- Diarrhoea
- Dark stools
The NHS states that most people should obtain the iron they need through a varied and balanced diet. It advises not taking high amounts unless directed by a GP.
Speak to a pharmacist or GP before taking an iron supplement when you have unexplained tiredness, heavy periods, digestive problems, are pregnant or suspect that you may be deficient.
6. A daily multivitamin
A multivitamin combines a selection of vitamins and sometimes minerals in one product.
It may be convenient for someone who wants broad nutritional coverage rather than a high-strength standalone supplement.
A multivitamin may suit people who:
- Have an inconsistent diet
- Want a simple one-product routine
- Prefer moderate amounts of several nutrients
- Do not want multiple separate supplement bottles
- Want to fill possible nutritional gaps rather than target one nutrient
A multivitamin is not automatically better than a targeted product. It may contain smaller amounts of individual nutrients, and the formula may include ingredients you already obtain elsewhere.
Before buying, check:
- Which vitamins and minerals are included
- The amount of each nutrient
- Whether iron is included
- The vitamin B6 content
- Whether it duplicates another supplement
- Whether it is suitable for your diet
- The recommended daily serving
7. Vitamin D
Vitamin D supports the maintenance of normal bones, teeth and muscle function. It should not be promoted as an instant energy supplement.
However, vitamin D is important to include in a UK supplement guide because government advice recommends that adults and children over four consider taking 10 micrograms daily during autumn and winter.
People with limited sun exposure and some people with darker skin may be advised to consider supplementation throughout the year.
Vitamin D is commonly available as:
- Vitamin D3 capsules
- Tablets
- Gummies
- Oral sprays
- Liquid drops
- Vitamin D3 and K2 combinations
Do not take high-dose vitamin D to address unexplained tiredness without seeking professional advice.
Which supplement is best for tiredness?
There is no single best supplement for every type of tiredness.
A practical way to narrow the options is to consider your diet and circumstances.
Consider a vitamin B complex when:
- You want several B vitamins in one product
- Your diet is inconsistent
- You prefer broad nutritional support
- You have checked that the vitamin B6 amount is appropriate
Consider vitamin B12 when:
- You follow a vegan diet
- Your diet contains few reliable B12 sources
- A healthcare professional has identified a low level
- You specifically want B12 rather than a full complex
Consider magnesium when:
- You want a mineral that contributes to energy metabolism
- Muscle and nervous-system support are also priorities
- You are comfortable comparing different magnesium forms
Consider vitamin C when:
- Your fruit and vegetable intake is limited
- You want a nutrient that contributes to reducing tiredness and fatigue
- You prefer capsules, gummies or powders
Consider iron only when:
- A healthcare professional has advised it
- Blood tests have indicated low iron or iron deficiency
- You have discussed persistent symptoms with a GP or pharmacist
Consider a multivitamin when:
- You want moderate amounts of several nutrients
- Convenience is more important than targeting one nutrient
- You have checked for unnecessary duplication
How to compare energy supplements
Do not choose a supplement based only on the largest number or the strongest wording on the front.
Check the active ingredients
Look at which vitamins and minerals are included and whether they are relevant to your reason for buying the product.
Check the amount per daily serving
The label may show information per capsule even when the recommended serving is two or three capsules.
Check the nutrient reference values
A percentage nutrient reference value helps show how much of the daily reference amount is supplied.
Providing several hundred or thousand per cent is not automatically necessary or more effective.
Check for duplicated ingredients
Ingredients frequently duplicated across products include:
- Vitamin B6
- Vitamin B12
- Vitamin D
- Magnesium
- Zinc
- Vitamin C
- Iron
Add up your intake when using more than one supplement.
Check the serving size
Consider whether you are realistically willing to take the required number of capsules, tablets or gummies every day.
Check dietary suitability
Look for clear confirmation of:
- Vegetarian or vegan suitability
- Allergens
- Capsule material
- Added sweeteners
- Artificial colours
- Gelatine
- Gluten or dairy information where relevant
Check the warnings
A responsible supplement label should include directions, warnings, storage instructions, responsible business details and a best-before date.
Food should remain the foundation
Supplements should complement a varied and balanced diet rather than replace it.
A balanced eating pattern should include a mixture of:
- Fruit and vegetables
- Wholegrain or higher-fibre carbohydrates
- Beans, pulses, fish, eggs, meat or other protein sources
- Dairy products or suitable alternatives
- Small amounts of unsaturated fats
- Regular fluids
The NHS Eatwell Guide recommends achieving an overall balance across the day or week rather than trying to make every individual meal perfect.
Other ways to support normal energy levels
Before assuming you need a supplement, consider whether your routine includes:
- Regular meals
- Enough fluids
- Consistent sleep
- Regular movement
- Time away from work
- A balanced diet
- Moderate caffeine intake
- Appropriate stress management
Large amounts of caffeine or energy drinks may temporarily reduce feelings of tiredness but can interfere with sleep and contribute to an ongoing cycle of fatigue.
When should you speak to a GP?
Arrange medical advice when tiredness:
- Has lasted for several weeks
- Is getting worse
- Affects work or everyday activities
- Does not improve with sleep or rest
- Is accompanied by weight loss
- Occurs with breathlessness or heart palpitations
- Is accompanied by weakness, numbness or pins and needles
- Occurs with significant mood changes
- Is unexplained
A healthcare professional may consider your symptoms, diet, medication and whether tests are appropriate.
Do not use supplements to delay seeking advice about persistent or severe symptoms.
Frequently asked questions
What vitamins are best for energy and tiredness?
Several B vitamins, vitamin C, magnesium and iron contribute to normal energy-yielding metabolism or the reduction of tiredness and fatigue. The most suitable choice depends on your diet and whether you have a low intake or diagnosed deficiency.
Does vitamin B12 give you energy?
Vitamin B12 supports normal energy-yielding metabolism, but it is not a stimulant. Supplementation is most likely to improve tiredness when low vitamin B12 is contributing to the symptoms.
Is vitamin B complex better than B12?
A B complex provides several B vitamins, while a standalone B12 supplement provides one targeted nutrient. A complex may suit someone wanting broad nutritional support, while B12 may be more appropriate for someone with a specific dietary need.
Is magnesium good for tiredness?
Magnesium contributes to the reduction of tiredness and fatigue and normal energy-yielding metabolism. This does not mean that it will correct tiredness caused by poor sleep, stress or an underlying medical problem.
Should I take iron when I feel tired?
Do not automatically take iron because you feel tired. Iron is most appropriate when there is a confirmed or likely need, and excessive iron may be harmful. Speak to a pharmacist or GP when you suspect iron deficiency.
Can a multivitamin improve energy?
A multivitamin may help fill nutritional gaps but will not necessarily improve energy when your nutrient intake is already adequate.
How long do energy supplements take to work?
There is no universal timeframe. It depends on the nutrient, your current intake and whether a deficiency is present. Supplements should not be expected to provide an immediate effect similar to caffeine.
Can I take magnesium and vitamin B complex together?
They are commonly found together in multivitamin and mineral products. Check the total amounts, particularly vitamin B6, and follow the directions on each label.
Are gummies as effective as capsules?
Both formats can provide vitamins and minerals when correctly formulated. Compare the active amount per serving rather than assuming one format is inherently better. Gummies may contain sugar or sweeteners and can require more than one per serving.
Are energy supplements suitable for vegetarians and vegans?
Suitability depends on the full formulation and capsule shell. Look for explicit vegetarian or vegan confirmation rather than assuming that every vitamin product is suitable.
Final answer
The best supplement for energy and tiredness depends on what your diet provides and why you feel tired.
Vitamin B complex offers broad B-vitamin support, while vitamin B12 may be particularly relevant to people following vegan diets or those with a low intake. Magnesium and vitamin C contribute to normal energy metabolism and the reduction of tiredness and fatigue.
Iron should be treated more cautiously and is best used when there is an identified need or professional recommendation.
Choose supplements using the active amount, nutrient reference value, serving size, dietary suitability and complete ingredient list—not marketing phrases promising instant energy.
Persistent tiredness should be investigated rather than managed indefinitely with supplements.