The pills to pop or not when it comes to your health needs

By The Gut Health Doctor Team

Dr Megan Rossi in a lab looking through a microscope

Do you struggle to know which supplements are science-backed or not? Although not an exhaustive list, it’s time to cut through the noise and provide you with some clarity on common supplement mistakes. 

Following on from my post where I spoke on This Morning about why more is not always better when it comes to supplements, I have been inundated with questions. To help support you, I wanted to tackle some of the common mistakes and things to be aware of so that you can make the most of the science.

There are more supplements out there than ever, particularly for gut health. While it’s great to see how people have latched onto the power of the gut, it’s disappointing to see so many companies and high-profile names jump on this bandwagon to sell misleading solutions that are not backed up by evidence. My goal is not only to help people feel more informed and empowered about their choices but also to assist them in reaching their health goals without wasting money or doing more harm than good. 

The truth is that feeling, and looking, your best does not need to be complex or expensive! And, when you do need that extra support or personalised guidance, then it is best to work with a healthcare professional or a registered dietitian to give you informed advice based on your individual needs (they’ll probably save you money too on unnecessary supplements and invalid tests). Much like you wouldn’t go to a personal stylist for dental advice, be cautious about who is providing you with nutritional science advice.

A photo of probiotic pills1. Probiotics

As many of you will know, this is an area I feel really passionate about because I did my PhD on probiotics (and prebiotics combined). To help empower you with the science, I’m going to give a free webinar on the latest probiotic research later in the year (I need to finalise reviewing all the research first!) — you can sign up here. The truth is, even if a probiotic is ‘high quality’ or ‘proven to survive’, most probiotics on the market are not only ineffective but they may exacerbate, or even create, issues like bloating. 

Much like medications, probiotics should only be considered in specific circumstances. Think of it this way, if you have diabetes, you wouldn’t take medication for arthritis, would you? The same applies here. 

Don’t waste your money on generalised probiotics ‘for good gut health’ no matter how convincing the ad is or how well an influencer sells it. There is no scientific evidence that taking a probiotic can support ‘general’ gut health. Eating more diverse plants is the best way to achieve that.

My other tip ahead of the webinar: before handing over your hard-earned cash (and potentially risking your gut health), always ensure there is a clinical trial to back the exact strain—aka the type of bacteria—in the probiotic. It should not be a collation of all different strains, as they can compete with each other. Additionally, make sure the probiotic strain is matched to the specific health issue you’re trying to manage.

A photo of someone holding up vitamin D towards the sun2. Vitamin D

Most of us know that government guidance is to take vitamin D during months that have limited sunlight, i.e. autumn and winter in the UK, Canada, most of the US, etc. However, what is less well known is the importance of the form of vitamin D and when to take it. I recommend taking vitamin D3 (aka cholecalciferol) as a recent review which included 20 studies, shows that it is more effective at raising your vitamin D levels. So when choosing a product, check the label and see if it’s this type, rather than D2 (the type produced by some plants, including mushrooms). However, if you only have access to D2 don’t stress, it’s still worthwhile taking and, with any vitamin D, you don’t need to go for an expensive brand.

You should also be aware that vitamin D is fat-soluble. That means it’s best to take it with a meal that contains some healthy fat to help support absorption from your gut into your blood. Healthy fats include extra virgin olive oil, oily fish (salmon, mackerel, anchovies, sardines, and herring), avocado, full-fat yoghurt, nuts and seeds. 

A photo of Omega 3 pills in a bowl3. Omega 3

Getting this from your diet is always best, but if you’re not able to have two servings of oily fish a week, then this might be one supplement worth considering. Algae oil is a good option for those following a vegan diet and one that is more environmentally sustainable, just ensure it contains both EPA and DHA (types of omega 3 fatty acids). But keep in mind, like most supplements there are contraindications because fish oil can increase your tendency to bleed, especially if you’re on blood thinner medication or have an existing bleeding disorder.

A photo of vitamin c tablets next to their packaging which reads 'Vitamin C'4. Vitamin C

There’s generally no need to resort to supplements for vitamin C when it’s easy to get more than enough of this nutrient from your diet naturally. For example, just ½ cup steamed broccoli contains over 80% of your daily needs. Also, high intake is a common cause of gut upset so it’s a supplement I rarely recommend. And, contrary to popular belief, the actual evidence that these pills can prevent colds and the flu is minimal too.

A photo of Iron pills spelling out 'Fe'5. Iron

I only recommend taking this as a supplement if a healthcare professional has confirmed you are deficient as, unfortunately, it can contribute to constipation. Check the product for instructions, but most are recommended to take on an empty stomach (or with a vitamin C-containing food or drink to increase the iron absorption). However, if it upsets your stomach, it is fine to take it with food but just avoid taking it alongside antacids, milk or calcium supplements as they can interfere with absorption.

A photo of turmeric and turmeric powder side by side6. Turmeric

This is a fascinating one! There is some interesting research, specifically on the active component curcumin, which shows an anti-inflammatory benefit, including for those with inflammatory bowel disease. If you decide to take this, make sure it’s combined with piperine, a compound found in black pepper, to help maximize absorption. I would say that this is one worth chatting to your healthcare professional about if you think you could benefit from it.

A photo of vitamin b pills in a bowl next to their jar which reads 'vitamin b complex'7. B Vitamin Complex

Although it’s unlikely to do any harm (as it’s water soluble which means it doesn’t store up in your body) it’s unlikely to do much good either. Have you ever noticed after taking this that you have extra yellow pee? That’s typically the excess B2 (aka riboflavin) coming straight back out! So if you’re having a generally balanced diet (remember it doesn’t need to be ‘perfect’) then it’s really not needed for most people.

A photo of a baby and child side by side, lying down on the floor8. Babies and kids

Most governments recommend all children aged from 6 months to 5 years old be given vitamin supplements containing vitamins A, C, and D every day. However, if your infant is having more than 500mls of infant formula a day then they don’t need vitamin supplements as the formula is already fortified with those nutrients. In addition, breastfed babies should be given daily vitamin D from birth (even if mum is taking vitamin D supplements).

Illustration of person considering dietary changes to improve gut health and help manage symptoms


As you can see, there are so many traps to fall into when it comes to supplements that it can be hard to know what is right for you. As a rule, I always say the best thing to do is to try and get the nutrients you need from a healthy and balanced diet (think 30 plant points a week along with fermented dairy and oily fish) before you turn to any extras. And, if you do need personalised support, then speak to a healthcare professional or a registered dietitian who can give you science-backed strategies tailored to your personal needs.

Please note that this is generalised advice and you should never replace the guidance from your healthcare professional who knows your individual needs. Many supplements are contraindicated with medication when pregnant and breastfeeding so always discuss with your healthcare professional (go in with a list of the supplement/s ingredients, as they can differ significantly by brand).

Bloating quiz illustration including stomach, test page and person looking at clipboard

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