Why you can trust Nutri Advanced  Every article on our site is researched thoroughly by our team of highly qualified nutritionists. Find out more about our editorial process.

Even for regular long-distance runners, completing a marathon is a huge achievement, and something that shouldn’t be taken lightly. Covering the distances required to prep for a 26-mile run involves much more than for a long run around the local park on a Saturday afternoon; you’ll require different gear, a strict training schedule – and, you’ll need to consider the way you are fuelling your body in order to limit strain.

The best supplements for marathon running, or the best supplements for marathon training, are simply those that will increase the levels of the vitamins and nutrients you already get from a balanced diet. Intense exercise can cause our levels to flag, meaning that many running enthusiasts will want to consider supplements for marathon runners. By adding a supplement into your daily regimen, you can ensure that your body is getting everything it needs in order to get the most out of your marathon running.Even for regular long-distance runners, completing a marathon is a huge achievement, and something that shouldn’t be taken lightly. Covering the distances required to prep for a 26-mile run involves much more than for a long run around the local park on a Saturday afternoon; you’ll require different gear, a strict training schedule – and, you’ll need to consider the way you are fuelling your body in order to limit strain.

So, what are the best supplements for marathon runners?

Do marathon runners need supplements? 

In short – no. No one needs supplements; providing that we eat a balanced diet and are properly hydrated, we can get every nutrient we need without having to take supplements. However, when participating in an exercise like marathon running, which goes on for a long period of time, it’s important to understand which nutrients your body will need the most.

So, when it comes to supplements for marathon runners, the best place to start is by understanding which vitamins and nutrients play a role in your exercise, and which might need a top-up to support your training.

Why do marathon runners consider supplements?

Unlike high-intensity workouts like weightlifting, running is all about endurance. Unless you can keep running at a decent pace for miles on end, you’re probably not getting the most out of your workout. Running, especially for long distances, takes your body to the limit of its endurance capabilities and then will push it even further. Of course, this also means that when you’re out running, you’ll need enough energy in reserve to keep pushing your limits.

Adding supplements to your diet will help your body to keep going mile after mile, hour after hour. Focussing on vitamin supplements for marathon runners will help you to be confident in the knowledge that you are putting the most into your training – and getting the most out of it.

What supplements do marathon runners take?

We’ve already taken a look at the best supplements for runners – but, marathon running is different: it’s longer, requires more endurance, and will take more out of you. So, the best supplements for marathon training will be slightly different.

The best supplements for marathon runners are ones that will help to support your body during long runs, and ones that help you restock to allow your body to recover during an arduous training schedule. In addition, beverages like electrolyte and caffeinated drinks will help you to support your performance, and help your body cope with the demands of marathon training.

Best supplements for marathon runners


Vitamins play a key role in nutrition, particularly when it comes to the best supplements for marathon training. They play a big part in endurance; vitamin C and B vitamins for example can help fight fatigue. Vitamin B12 is required for energy production in cells and because vitamin B12 can only be found naturally in animal products, runners who follow a vegan or vegetarian diet may particularly benefit from taking a multivitamin to maintain energy levels.


Running, and any other endurance exercise, will deplete glutamine levels in your muscles and blood stream. And, as glutamine acts as fuel for immune cells, your immune function will be limited if your levels decrease.


L-Carnitine helps your body to transfer long chain fatty acids to be oxidised for energy production, powering muscle contraction. It helps to provide your body with extra energy, and is used by a variety of different athletes to support performance.

Omega-3 fatty acids

We recommend Omega-3 to everyone – not just marathon runners. It helps to support your heart, brain and vision, as well as benefiting joint health. Therefore, it’s a crucial feature on our list of best supplements for marathon running. This is a nutrient our bodies don’t naturally produce, so the only way we can get what we need is by eating oily fish, or taking a supplement. We even offer a vegan alternative, to ensure maximum levels regardless of dietary requirements!


Iron is an essential nutrient, which means it must be consumed because we can’t manufacture iron internally.  Vegetarian and vegan runners are at an increased risk of lower iron levels because the richest and most readily absorbed sources of iron are from animal meats.  If you are a marathon runner, adding an iron supplement could be useful, particularly if you are vegetarian or vegan, or your diet is low in iron, or you have higher requirements e.g. women in their reproductive years.


No list for any runner would be complete without calcium. Calcium is crucial in the support of bone health, and considering running puts a lot of stress on your skeletal structure, it’s important to ensure you are getting your recommended daily amount.

Zinc and magnesium

When it comes to the best supplements for marathon runners, zinc and magnesium have to make the list. Magnesium helps to transport energy around your body, and zinc helps you to metabolise energy so you can put it to good use.


Ashwagandha is a traditional ayurvedic herb known to increase energy and support the stress response. If you are a marathon runner, adding an ashwagandha supplement could be useful as it helps increase the capacity of the blood to transport oxygen to exercising muscles to enhance your performance.

Marathon running with Nick Bester

We have been lucky enough to have a chat with Nick Bester, a seasoned marathon runner with 45 marathons under his belt. Discover what Nick thinks about marathons, training, and what the best supplements for marathon runners are.

Can you introduce yourself to our readers?

I’m Nick Bester, also known as ‘Justalilbester’. I’m an athlete and a running coach. I’m on a mission to try and break 2h 20m in the marathon distance. I’ve come close but still need nine seconds in order to crack it. I started an athletics club in the UK called Best Athletics. It was registered just under two years ago and they are currently 320 members. A club I’m very proud to be a part of end represent. I am also a coach and London captain for Adidas.

How long have you been running, and how many marathons have you completed?

I’ve been running for 9 ½ years now. Since the start of my journey I’ve completed 45 marathons and 12 ultramarathons. Hoping the next marathon will be my fastest.

What are the biggest challenges that runners face?

I would say this to big challenges here the first of which has to be injuries. Unfortunately, in the running game Nichols and injuries play a big factor. But it’s part of the reason that keeps a lot of us coming back for more. If it was easy, you wouldn’t get that same satisfaction that you do after getting to your best levels coming back from injury. The other big challenge I would say is lack of motivation. It’s difficult to put in the work day in and day out. So by joining people, following a plan, or building up to race, those factors make it a lot easier.

Have you been injured before? If yes, what sort of injury? How did you overcome it?

Yes I have. In fact almost all runners have. My biggest injury was when I stress fractured my tibia. They put me out for eight weeks. However during this time I was still able to cross train, which helped me maintain fitness, and made my return to running a whole lot easier.

Do you have any advice on how to avoid injuries?

Three things have popped to mind:
1. Smart training and sticking to the correct structure. Recovering properly on easy days.
2. Fuelling sufficiently through our training and for sessions.
3. Strength work is crucial. Getting the body and legs strong enough in order to sustain training.

Do you stick to a strict nutrition plan? If so, do you take any vitamins or supplements?

I don’t follow a nutrition plan specifically, but I try keep my diet clean especially during vigourous training and then the buildup to race. I’ll take the following vitamins and supplements on a daily basis:

- Recovery protein within half an hour of the session.
- Hydration electrolyte tablets.
- MegaMag Muscleze ease before bed.
- Omega-3, vitamin B, vitamin D and calcium.

If you could give nutritional advice to a new marathon runner, what would it be?

Give yourself the sufficient amount of fuel your body needs. Fuelling correctly is as important as training. If you get your fuelling right, you’ll feel way better in sessions, hit better times, and speed up overall improvement. The two bits of nutrition I take daily, religiously, without fail, is recovey protein after sessions, and MegaMag Muscleze before bed. Look after your body, and it will look after you.

This website and its content is copyright of Nutri Advanced ©. All rights reserved. See our terms & conditions for more detail.

Nutri Advanced has a thorough research process and for any references included, each source is scrutinised beforehand. We aim to use the highest value source where possible, referencing peer-reviewed journals and official guidelines in the first instance before alternatives. You can learn more about how we ensure our content is accurate at time of publication on our editorial policy.