Being a vegan made me ill - when I stopped, my health problems vanished overnight (2025)

Some topics simply can’t be mentioned on social media or in polite company, for fear of triggering a volcanic debate – and I’m not talking about Trump or the Middle East. Because as every vegan and ex-vegan knows, nothing is more divisive than choosing to avoid animal products.

Nutritional science occasionally throws a research bomb into the mix, too, and this week the anti-vegans have the advantage, as it now appears that around 50 per cent of long-term vegans could be at risk of muscle wastage.

The New Zealand based study, from Massey University, followed 200 strict vegans and found that half were lacking two vital amino acids. Lysine and leucine are found in animal proteins such as eggs and meat, and are essential for building muscle and turning fat to energy.

But while the vegans were following government guidelines on plant-based nutritional balance, the research found that plant foods contain less of the amino acids than animal products, and that only a small amount was absorbed in plant form. The study’s author, Patricia Soh explained: “Prolonged deficiencies in these essential nutrients can negatively impact body functions, including muscle mass maintenance.”

Even with the caveat that this was a small study, the findings are worrying – particularly when it comes to perpetuating the idea of the pale, weedy vegan, who can barely muster the strength to lift a carrot to their chapped lips.

I say this from a position of slight defensiveness, because for four years, I was a vegan. I edited a glossy vegan magazine, and delighted in creating fabulous meals without animal products. I knew all the dangers of a restricted diet and was awash with vitamin B12, iron and zinc supplements. I had cupboards full of super-healthy pulses, whole grains and the much-vaunted “dark, leafy greens” and you could inscribe what I didn’t know about chia seeds on top of one.

I filled the magazine with plant-based inspiration, including champion weightlifters, runners and mountain climbers – all of whom were vegan.I had long been vegetarian, but going vegan myself was, I thought, the next step in my lifelong love of animals. There was no going back. Or so I thought.

About 18 months into my diet of soy products, dark leafy greens, pulses and occasional dark chocolate, rather than a glowing temple of health, I was starting to feel like a dilapidated shed. I had developed a rash on my limbs, my gums bled every time I brushed my teeth, I experienced bouts of itching that I’d never had before, and my hair, never luxuriant, resembled Garth from Wayne’s World auditioning for Worzel Gummidge. I also felt very tired. I couldn’t summon up the will to exercise, and I always had an excuse – it was raining, I was too busy, the local pool was closed.

I’d also become perimenopausal, so every weird symptom and bout of exhaustion could very easily have been my hormones causing havoc. I found it impossible to imagine that it could be my diet causing all this. According to everything I knew, it was pure wholesomeness. I went back and forth to the GP, I was referred for tests, at one point, they even sent me to oncology to check for cancer. All the while, I merrily scoffed tofu, nuts and black beans.

It wasn’t until I was offered a full allergy test, which required me to have little plugs of allergens stuck all over my back for a day, that I was diagnosed. I had a “severe” nickel allergy. Nickel, apparently, is found in most vegan foods (such as soy products, peas, canned foods, cashews, nuts, seeds, whole wheat, oats, and certain grains) – but not in animal products. Basically, I had been OD-ing wildly on it, and triggered a dormant allergy.

“But I have to be vegan,” I told the consultant.

“Don’t be so silly,” he said.

No matter what, I couldn’t bring myself to eat meat – basically driven to bitter tears at the sight of a sad farm animal. But in light of this news I pretty much had to re-introduce fish, eggs and cheese, rather than starve. I also returned to prawns for iodine and zinc, after a 20-year absence, as I judged them to be less intelligent than crabs and lobsters (I still can’t do crustaceans).

The first time I ate fish, a little piece of salmon, I won’t lie, it was glorious. I shoved the guilt to the back of my mind, and enjoyed it. And after a couple of weeks of cheese, milk and eggs too, I felt a great deal better. My symptoms vanished almost overnight, and my energy returned.

Now, four years later, I am still not eating meat (I never will), and fretting about sustainable fish and free-range, organic eggs – but I am eating them. I’ve come to believe that while a balanced vegan diet suits some people perfectly, the majority of older people will struggle to get enough of the right nutrients on a purely plant-based diet. I wish I could, but as a now post-menopausal woman, I know how hard it is to eat a balanced, healthy diet as it is, without stripping away entire food groups.

And I feel better, I exercise (regular yoga, walking and swimming) and I don’t worry about whether I’m eating enough protein via almonds, marinated tofu and edamame beans – I just have a bit of cheese on toast.

Nichola Ludlam-Raine, a specialist dietician and author of How Not to Eat Ultra-Processed, says, “the findings of this study highlight an important aspect of plant-based eating: protein quality. The study shows that amino acids can be limiting in plant-based diets. It’s not just about total protein intake, but also about its digestibility.”

To support muscle health, she adds, “focusing on protein quality and potentially incorporating more quinoa, legumes, soya and pulses can help mitigate these risks, as well as supplementation using vegan ‘blends’ of protein powders.”

I know lots of vegans who are sure they get more than enough protein. And I know there probably are ways the non-allergic can supplement their plant-based diets and be perfectly healthy and live forever (or at least, it’ll feel like forever). But in the end, it wasn’t for me – and if this study proves correct, we might need to entirely rethink our approach to plant-based eating – even if that means our halos slip a little in the process.