Subscribe to our newsletter to receive news and inspiration direct to your inbox

Pill popping

Nutritional therapist and author Petronella Ravenshear explains the three supplements that everyBODY should be taking

5 January 2024

So you know you could be healthier. You want to be healthier. You go to a health food shop – a good one, with people who know things about being healthier – and you are met with aisles and aisles of supplements that could bring an improvement to your waistline/hairline/sleeping hours/waking hours/stress levels/sugar levels/blood/bones/skin/nails/sex life/work life… And maybe you buy something recommended by an in-the-know friend or salesperson. Or maybe you buy everything, because what if you need everything?!

If you are not one of the few who can parse the masses of often conflicting information on the subject, it’s a case of what we call ‘supplementation frustration’.

So we asked Petronella Ravenshear, author and nutritionist to fashion and celebrity insiders, and long-term Chelsea resident, for her ultimate desert-island pick of the three supplements that every person should be taking. 

And she’s certainly qualified to speak on the matter: Petronella trained for three years to become a nutritional therapist, opening her private practice in Chelsea in 2004.

Her remarkable work in helping people who struggled with lifelong health and weight problems inspired her book The Human Being Diet (fully revised in 2023), which has resulted in some phenomenal transformations and evolved into a thriving community of devotees as readers have followed her method to drop weight on their way to reclaiming optimum health.

So, you can forget the supplement-related analysis paralysis, because these are the three supplements that Petronella recommends for everyone…

That old mantra about getting all the nutrients we need from the food we eat – it’s just not true anymore. It’s clear that the government doesn’t believe it either because much of our food has been mandatorily fortified with vitamins and/or minerals, from table salt to flour, for the past 80 years. 

We’re overfed and undernourished at the same time – it’s estimated that 60% of calories in the average person’s diet are derived from ultra-processed foods, which deliver little in the way of nutrition.

Petronella Ravenshear

Intensive farming has resulted in more of our food being grown in nutrient-deficient soils, and that translates into less nutritious foods on our plates. At the same time, we are faced with environmental pollution from pesticides and other toxins, not to mention our persistently high levels of stress. 

All these factors mean that now, more than ever, we need to protect our health by supplementing the nutrients our bodies need to function at their best. When we give our bodies what they need, the result is that we have more energy and get more joy out of life. And these are three of the key nutrients that so many of us are deficient in:


Fatigue, insomnia/poor sleep, low mood, muscle cramps or tremors, headaches, arrhythmia, poor circulation, high blood pressure and anxiety.


Magnesium is key for energy, for a sunny outlook on life and for heart health. And we need much more of it when we’re under stress. Almost every cell in the body needs magnesium to function properly. It can help with constipation too.


Supplements containing organic forms of magnesium such as magnesium citrate, glycinate or malate are the best and most easily absorbed. My favourite is Bonusan Magnesan Forte available online at the Natural Dispensary. Take 400-600mg in divided doses (e.g. two tablets with breakfast and one with dinner). An Epsom salt bath (add at least two big cups to a hot bath and soak for 10 minutes or longer) is a great way of supplementing magnesium too – we soak it up through our skin. Avoid taking magnesium without first consulting your GP if you have kidney disease.

Vitamin D

Low mood/depression, lowered immune function, muscle cramps, feeling the cold, inflammation and sore joints.


A big portion of the population is thought to be vitamin D deficient. Correcting a vitamin D deficiency is likely to make you feel better, both physically and emotionally.


Make sure your vitamin D is in the form of D3 rather than D2. Allergy Research Vitamin D3 Complete (available at Revital, King’s Road) is excellent as it combines D with the other fat-soluble vitamins E, K and A, which work synergistically together. 

Because sunshine is the only meaningful way to obtain enough vitamin D, northern hemisphere countries such as the UK would be well advised to take 2000iu every day with breakfast. You may need more than that, a blood test is highly recommended – avoid high doses of vitamin D unless you know that you need it.

DHA and EPA (omega-3 essential fats)

Dry eyes, dry or rough skin, depression, poor concentration and memory, pain.


It’s vital for brain, heart and eye health and strengthens immunity, as well as reducing inflammation. The World Health Organisation tells us that 74% of annual deaths worldwide are due to avoidable lifestyle diseases which involve inflammation – so getting inflammation under control is vital for good health. And this oil is good for skin and hair too.


Bionutri Fish Oil 5:1 is higher in DHA than EPA and an excellent choice – I take two with breakfast. If you follow a plant-based diet, Bionutri also makes Vegan DHA (which comes from algae) – both are available at Revital, King’s Road and 2g daily is a good dose of omega-3 as DHA and EPA. We cannot get the precious omega-3 that we need by eating nuts and seeds – the DHA and EPA we need is only provided by oily fish or algae supplements.


You can buy Petronella’s book The Human Being Diet at or on You can also follow her on Instagram at @PetronellaRavenshear for inspiration, recipes and guidance.

Discover more

Immerse yourself in the fascinating world of Sloane Street with our selection of insightful articles