Nutritional expert Tim Spector has provided insight into the power of diet on our body’s defence mechanisms against viruses and the potential to ward off serious repercussions such as long Covid. The professor of genetic epidemiology at King’s College London and creator of the Zoe health app, he suggests a close connection between our immune system and gastrointestinal health – pinpointing inflammation as a major culprit behind severe complications.
Elaborating on this pivotal relationship, Spector emphasized the importance of a thriving gut microbiome for robust viral resistance – particularly against pathogens like Covid-19 – while also preventing an excessive immune response that is often implicated in prolonging symptoms experienced with long Covid. He explained: “We now know that most of our immune system is in our gut and the way it gets its signals, and it understands what’s going on around it is through the gut. Microbes healthier your gut microbes.”
Adding that, “The more diverse they are, the better you’re going to be able to control your immune system. And this means it’s going to react appropriately to, say, a covid virus. It’s going to try and kill it, but without overreacting and killing you.”
“So people eating a junk food is going to have an inflamed gut microbiome that’s trying to put out fires all over the place. And so when a real virus comes along, it’s not able to pin it down. So if you want to have the best immune system, you need to make sure your gut health is in the best possible way. I can’t stress enough. It’s plant diversity. It’s fermented foods, and it also means not having ultra processed foods and getting plenty of fibre in there.”
Prof Spector warned that pandemics are becoming increasingly frequent and severe, urging people to reconsider their diets in preparation for future ones. The nutritional scientist has called for certain foods to be removed from our diets, and those of our children, as the UK now “leads Europe in ultra-processed food consumption, with a staggering 57% of our daily food intake coming from these products”, reports Surrey Live.
According to Tim, ultra-processed foods are “edible food-like substances” which take the ingredients from real food, then strip away key components such as fibre, since it can’t be easily manipulated. “They take the essential extracts from food and they combine them in different ways,” he explained.
“They have to add glues, chemicals and additives to stick stuff together and to make it look like food again.”
Prof Spector has recommended that people should aim to consume 30 different types of plants every week and is a strong supporter of fermented foods like kefir for gut health. He explained the numerous benefits of such foods, stating: “In particular, they seem to support your immune system, which is so vital to fighting allergies, infections, cancer and ageing, thanks to their interaction with your resident gut bacteria.”
However, he warned against indulging in sweetened, additive-rich yoghurt once a week, emphasising the need for quality products consumed in small amounts throughout the day.
He cited a US clinical study which found that individuals who ate four to five small servings of fermented food daily showed significantly improved blood markers of inflammation and immune function after just two weeks. “So, if you have one or two portions daily, you will likely also benefit.”