How a change of diet can add years to your lifespan

Scientist and nutritionist Dr Federica Amati wants to show us how to eat our way to a long and happy life with her book ‘Every Body Should Know This’,

Scientist and nutritionist Dr Federica Amati

“One in five deaths globally could be prevented with improved diets.”

Dr Federica Amati doesn’t pull any punches in her book Every Body Should Know This: The Science of Eating for a Lifetime of Health. As well as being a scientist, she is a gifted and passionate communicator who believes that teaching people about the importance of nutrition can change — and save — lives.

While there are many sources of (often conflicting) nutritional advice available, especially on social media, Amati — who has a healthy Instagram following of some 21,000 followers — is someone who knows what she’s talking about. She holds a PhD in clinical medicine research from Imperial College London, lecturing medical students about nutrition, and is head nutritionist for the personalised nutrition programme ZOE. She knows that food can make a difference to everyone’s health, at every age, and she is committed to getting this message across in an accessible way.

When she spoke to Irish Examiner, she had just learned that her new book had become a Sunday Times bestseller. “Having a bestseller is a great accolade, but it’s great that this [book] is something that is resonating with people and that they are interested in it,” says Amati.

It’s an engaging read, full of intriguing facts and some hard truths: There’s no such thing as one ‘superfood’, and what children and young people eat has an impact on their health now and in the future, an average adult gets about twice the amount of protein they need from food alone (no bars or supplements necessary), you’re never going to look like you’re 20 when you’re in your 80s, no one can biohack their way to immortality (no matter how many billions they have) and we all need to move and sleep more.

She has noticed that people often read Every Body Should Know This in a particular way: they turn to the section most relevant to their age group first before reading the rest of the book and discovering things that enable them, as she notes, to “best support other people in their lives at different life stages”.

The book spans the life cycle, focusing on specific windows of opportunity where good nutrition can make a real difference to long-term health. The key areas Amati looks at are a baby’s first 1,000 days of existence, puberty, young adulthood, the twilight zone (from 50 to 70), and the years beyond. She explains why we need to eat differently at different life stages, how this can be achieved, and why this can make a difference to our overall health.

Every Body Should Know This: The Science of Eating for a Lifetime of Health

It’s never too late to start. Amati quotes World Health Organisation research on how dietary change can make a difference in lifespan: “A woman in her 40s can gain over 10 years of life by switching from an unhealthy standard diet to a healthy, Mediterranean-style diet. A man in his 70s can add five years.”

The scientifically tried-and-proven Mediterranean diet, which includes lots of vegetables, fruit, whole grains, fish, legumes and olive oil, has been consistently studied and linked to a lower risk of heart disease, diabetes and even depression. In her book, Amati writes that this diet is “a beneficial pattern of eating we should all be adopting and making available through public health interventions in schools and hospitals.”

Coming from an evidence-based, scientific background, Amati wants to help readers navigate nutritional misinformation on social media: “There’s just so much noise on TikTok and Instagram — lots of harmful things for nutrition and mental health.” Some social media posts are a bit random but harmless, she adds. “That raw carrot salad trend? It’s not a magic fix for hormones but at least it won’t harm anyone.”

She feels it is important to teach people to navigate the nutritional minefield by encouraging them to take a scientific approach, ask questions, and query food solutions that come with big claims and large marketing budgets.

While Amati writes about particular nutritional needs at different stages of life, she consistently recommends whole foods, home cooking and avoiding ultra-processed foods. She is adamant that lack of time is not an excuse for bad nutrition.

“Prioritise time for cooking food [from scratch],” she says. “It only takes about one hour to make and eat very delicious food, less time than we spend on social media. Invest that time in yourself.”

Amati wants to help people understand that “food is an important tool for health, but it is also an important tool for connections, enjoyment and joy”. She knows, scientifically, that “food is a measurable tool” that decreases the risk of disease, but it does not exist in a vacuum: “Joy and happiness are just as important and also contribute to a longer life.”

She hopes her book will help “people connect with the power of food to transform their health for today and the future and to take joy in food”.

This is no small ambition for Amati, but the scientific evidence she lays out in Every Body Should Know clearly shows that the benefit of spending time preparing and eating nourishing foods is a tangible investment in your and your family’s health.

Every Body Should Know This: The Science of Eating for a Lifetime of Health by Dr Federica Amati is published by Penguin (€19.99 in paperback).