Best Keto Supplements UK 2025

10/01/2025 By Dylan Kitson

Helping you to discover the Best Keto Supplements UK in 2025…

The ketogenic diet is simple; eat a low-carbohydrate, high-fat diet to switch your body into a natural state of ketosis. This changes how your body fuels itself, telling it to switch to ketones instead of carbs as fuel.

Keto supplements can aid your body in a variety of ways; they can directly improve ketosis and support your physical health, potentially even making the keto diet less risky to undertake! We’ve picked out a range of keto supplements you should consider buying and given our opinion on some supplements that aren’t worth your money as well. Our Best Keto Supplements UK of 2025 should help you find the best keto supplements for you…

After reviewing dozens of supplements, we believe that Performance Lab MCT is the best MCT oil for keto currently available on the market.

Visit Performance Lab’s Website here

Or read on to learn why we chose this MCT oil as our #1 recommendation in our list of Best Keto Supplements UK.

Table of Contents

Why Follow a Ketogenic Diet?

People follow a keto diet for a variety of health reasons. It’s been shown to lower blood sugars, reduce blood pressure and, most importantly of all, promote weight loss in clinical studies. Keto has been hailed as a weight-loss wonder diet and unlike some other popular diets, there’s scientific research to back up keto’s effects. It has been shown to significantly reduce body weight and body mass index (BMI) in multiple studies; people typically lose around 10kg over an 8-week period [1].

This amazing weight loss can be great for your health and confidence, but there are potential side effects too, like keto-flu[2]. So-called because the symptoms are flu-like, this tends to occur at the start of the diet, when the body is getting used to a diet with very few carbs (a typical keto diet tends to include less than 50g of carbohydrates a day). [3] You may experience withdrawal-type symptoms, mild or severe, which typically last a week for most people.

Some of the keto supplements in this Best Keto Supplements UK list may help with this. An MCT oil, for instance, can help you to reach ketosis quicker and more efficiently. Other supplements, like magnesium, can fight off keto-related side effects. Some of the other keto supplements listed here may help to further improve your results from keto.

We’ve studied hundreds of supplements and picked out the Best Keto Supplements UK 2025.

Best Keto Supplements UK That Actually Work

MCT Oil

MCT Oils are one of the most popular keto supplements. Medium Chain-Triglycerides (MCTs) are small, healthy fats that have been shown to aid weight loss in multiple scientific studies. MCTs are converted into ketones – this means they can directly improve ketosis. They can also decrease your appetite and help you feel fuller for longer. [7] If you’re embarking on a keto diet, investigate using an MCT Oil supplement. We believe a quality MCT oil should be on your list of Best Keto Supplements UK.

WE RECOMMEND… Best MCT Oil in UK in 2025

We like Performance Lab MCT Oil as it contains C8 and C10, the two most powerful MCTs. It’s made from organic coconuts and doesn’t contain any unnecessary ingredients.

It’s also 100% MCTs – many other similar products contain 90% or less. You could also buy an MCT Powder, but they’re not as handy – powders must be mixed into a drink first, while MCT Oils can be used without prior preparation.

BUY: Performance Lab MCT

READ: Our Full Review on Performance Lab MCT

Magnesium

Magnesium is a great keto supplement, especially if you’re starting a keto diet. Taking it may help fight off the dreaded keto-flu as mentioned above, a non-serious side effect experienced when people begin a low-carbohydrate diet. Keto-flu is not a real disease; it’s a collective term for headaches, sugar cravings and fatigue that can occur during keto. It occurs when magnesium levels drop as the body adjusts to ketosis so taking magnesium could alleviate these symptoms. Even if you’re flu-free, keep an eye on your magnesium intake to ensure you don’t become deficient. Many keto-friendly foods, like spinach and kale, are naturally high in magnesium so you might already be getting your recommended daily dose of magnesium (which is around 350mg for adults). [4]

We recommend: If you’re looking for a quality standalone magnesium supplement, we’d like to recommend Performance Lab again. Its Performance Lab Magnesium is clean, effective and made to the highest standards.

Omega-3

Omega-3 is a popular supplement that’s taken for a wide variety of health benefits; it may reduce cholesterol, manage high blood pressure and help you lose weight. It’s extremely useful for anyone on a ketogenic diet, as we’re about to explain.

Omega-3 contains health-promoting polyunsaturated fatty acids. The risk of following a high-fat diet such as keto is that your diet tends to be higher in omega-6 fatty acids and lower in omega-3, which can promote inflammation in the body.

Omega-3 supplements, therefore, can be beneficial for people on ketogenic diets, helping them to maintain healthy omega 3 – omega 6 ratios. Taking omega-3 while following a keto diet has been shown to ‘improve the positive effects of a ketogenic Mediterranean diet’.[5] This scientific study used volunteers on a Mediterranean diet, but we see no reason why it shouldn’t work with other keto cuisines. Most Omega-3 supplements are made from fish oil, which isn’t ideal, but you can find seaweed and algae-based Omega-3s as well, such as…

WE RECOMMEND… Performance Lab Omega-3

As you can probably tell, we’re fans of the top-quality Performance Lab range here at Supplement Reviews UK. They’re renowned for creating effective, safe and clean supplements with quality ingredients and ingenious solutions. We’ve chosen Performance Lab Omega-3 partly because it will stack perfectly with Performance Lab MCT, but also because it’s a superior supplement in its own right.

Here’s why Performance Lab Omega-3 is so highly rated: it gains its Omega-3 from its original source, algae. Fish get their Omega-3 fatty acids from eating algae, but that means a lot of other fish oil supplements taste and smell, well,… fishy. Performance Lab Omega-3 cuts out the middle bit and goes straight for the prime source. As a result, it doesn’t taste fishy; doesn’t threaten fish stocks; is incredibly clean and ethically manufactured; vegan-friendly, and is the best Omega-3 supplement available to buy on the UK market today.

For all the reasons above, it deserves its place on our list of the Best Keto Supplements UK in 2025…

BUY Performance Lab Omega-3

Read: More on the benefits of Omega-3

Vitamin D

Vitamin D is an essential vitamin; our body uses it in loads of different ways so it’s important to get your daily recommended dose (which is around 10mg).

Many people don’t have enough vitamin D in their diet, increasing their risk of developing osteoporosis and muscle weakness. Around 50% of the world’s population has a vitamin D deficiency, most people simply don’t realise it. The UK government recommends everyone supplement with vitamin D in the winter and autumn months as the sun isn’t strong enough to produce enough vitamin D in the body at this time.

If you’re on a keto diet, vitamin D deficiency could be holding you back. This is because not having enough vitamin D in your diet negatively affects keto weight loss [6]. Taking a Vitamin D supplement could help you lose more weight in a shorter period and even if you’re not trying to lose weight, it’s a useful keto supplement to take. Making it a crucial part of our Best Keto Supplements UK.

Calcium

A lot of calcium-rich foods, like dairy products, are high in carbohydrates – it’s difficult to include them in a keto diet. This means you need to find a good low-carb alternative. Poppy seeds and salmon are great examples but they’re expensive. A calcium supplement might be a better choice as they’re cheap and provide you with a precisely measured daily dose of calcium. The body uses calcium in all sorts of ways, but it is especially important for bone and teeth health. There’s some evidence to suggest keto diets put some people at a higher risk of developing weaker bones [8]. To mitigate this risk, take a calcium supplement as part of your keto lifestyle.

Fibre

When it comes to digestion, fibre is fundamental. It isn’t absorbed or digested like most food components; it remains in the digestive system, helping to control blood sugar levels and maintain good bowel health. A ketogenic diet can confuse your digestive system, especially in the first few days – irregular bowel movements are a common side effect of this. Including dietary fibre in your keto diet will help keep you regular and generally keep your gut happy and healthy.

Fibre supplements are one of the cheaper supplements on the market – a 500g tub typically costs around £6.00. Many supplements use fibre to bulk out their products and bind them into tablets or capsules. A lot of keto supplements contain loads of fibre, even if it isn’t listed as a major ingredient. Eating fruit and vegetables daily will provide most people with adequate dietary fibre – we don’t consider fibre supplements necessary for most keto dieters, but they can help aid digestion and fend off constipation. Non-starchy vegetables such as bell peppers, broccoli, green beans, cauliflower and courgette are best for keto as they are low in carbs but high in fibre.

Multivitamins

There are more than 30 minerals and vitamins the body needs to function correctly. Ensuring you get enough of each of these can be a challenge. Unless you eat an extremely varied diet, you might not be getting your recommended dietary allowance of these different micronutrients. Multivitamins are a quick and easy solution to this problem. They’re generally inexpensive and easy to find online and in shops.

There are hundreds of multivitamins, but which is best suited for a keto dieter? As men and women have slightly different biological demands, we recommend taking a gender-specific multivitamin.

WE RECOMMEND… Best Multivitamin in UK 2025

We recommend another product from the Performance Lab line for this – Performance Lab NutriGenesis Multi for men or women (two options, tailored to gender). Performance Lab is one of our favourite manufacturers for their effective, clean supplements and their commitment to ethical, transparent and quality-proven manufacturing.

Performance Lab NutriGenesis Multi contains nature-identical nutrients that are easier for the body to absorb. This makes it superior to almost every other multivitamin supplement – many of its competitors typically use cheaper, synthetic nutrients instead. It is slightly pricier than other multivitamins, but we believe it’s better to invest in a superior quality product rather than a low-quality cheaper option.

BUY: Performance Lab NutriGenesis Multi

READ: Our Full Review on Performance Lab NutriGenesis Multi

Caffeine

Caffeine helps most of us wake up in the morning and stay alert throughout the day. As well as boosting your energy levels, your morning cup of coffee could also enhance your keto diet! Research has shown that caffeine can boost ketone levels by around 88%, although more definitive research is needed.

Many people who’ve tried a keto diet mention an improvement in their energy levels, especially after the first few days. Unfortunately, keto can also cause a dip in energy levels as your body switches to ketosis, leaving you feeling lethargic and snappy. Caffeine can keep you feeling awake and spritely. Although tea and coffee are often the go-to sources of caffeine, there are other, better ways to consume it. A caffeine supplement gives you a measured, effective and budget-friendly dose of caffeine without having to wait for the kettle to boil!

Here’s where you can make another great Performance Lab stack — Performance Lab MCT Oil + Performance Lab Caffeine 2 (a gentle dose of 50mg of caffeine per pill, allowing you to choose how much to take). Both products are designed to be used together safely.

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Supplements That Don’t Work

You might be persuaded to buy some of the supplements below – but don’t be fooled! We’ve done our research and decided that these supposed keto supplements probably won’t help your keto diet. Some of them do have scientifically-backed uses; for example, digestive enzymes supplements can alleviate enzyme deficiencies [9]. However, they aren’t advantageous to the typical keto dieter.

Exogenous Ketones

Ketones are the special molecules that are used by the body during ketosis. You might think that taking a ketone supplement would help you reach ketosis quicker, but this isn’t the case. One study has found that exogenous ketones don’t significantly affect weight loss, so we currently don’t recommend taking them [10]. There is some evidence to suggest taking them could slightly decrease your appetite [11], but there isn’t any conclusive evidence that exogenous ketones can benefit keto. Exogenous ketone powders, tablets and capsules can cost a lot of money and don’t provide enough beneficial results to justify the price.

Digestive Enzymes

The human body has evolved to function without needing extra digestive enzymes – you can manage perfectly fine without taking an enzyme supplement. Enzymes in the stomach and intestines break down food and process it into energy and new proteins. They play a massive role in digestion but there’s no need to increase the level of digestive enzymes. In our opinion, digestive enzyme supplements aren’t useful for keto diets.

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Athletic Performance and Keto

The ketogenic diet is suitable for healthy adults of all ages and fitness needs. However, keto can be especially useful for athletes and athletic performance. Endurance athletes like cyclists and runners have been turning to keto in recent years to improve their performance. If it works for pro-athletes like Michael Andrew and Zach Bitter, it should work for you too! There is a range of supplements available to boost athletic keto performance.

BCAAs

Branched-Chain Amino Acids (BCAAs for short) are a blend of three amino acids: valine, leucine and isoleucine. You can’t build proteins and muscle without them; this makes BCAAs especially popular among bodybuilders. Even if you’re not looking to build muscle, BCAAs could be of use; they have been shown to cause a minor increase in fat oxidation. This means BCAAs could help you lose weight while on keto [12]. BCAA powders are fairly inexpensive, costing around £5.00 per 100g while BCAA capsules fetch higher prices.

Creatine

Creatine is great for creating new muscle and supporting existing muscle mass. It naturally occurs in the body’s muscle cells where it helps produce ATP, the ‘energy chemical’ that powers pretty much all biological processes in the human body. Creatine is one of the most frequently studied supplements and multiple studies agree that taking it can boost muscle growth and give cells more energy. It’s not an anabolic steroid or any other dangerous synthetic supplement – creatine is 100% natural and safe for most people to take.

One troubling side effect of a ketogenic diet is muscle loss. There’s a lot of anecdotal evidence suggesting linking muscle loss to keto but there hasn’t been much scientific research into this problem. Taking creatine could decrease your chance of experiencing this worrying side effect and it may even allow you to build muscle instead!

HMB

HMB — beta-hydroxy beta-methylbutyrate – is created in the body when leucine is broken down and is known to reduce muscle breakdown. This can be especially important for those people who want to increase their exercise intensity while on keto, or who want to start an exercise programme. A key part of a ketogenic diet is reducing the amount of protein you consume, which is typically the go-to macronutrient for building and preserving muscles[13], so HMB can go some way to filling this void.

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