There’s no such thing as the average human, so there’s no one right way to eat

We all want to be healthy. Our government wants us to be healthy too. That’s why they issue guidelines about how to eat and how much exercise to do.

The problem with these guidelines is that food is complicated, and so are people. Even more importantly, these recommendations are based on what the ‘average person’ needs.

And that ‘average person’ doesn’t exist.

Meet Ms Average

Meet Average Mary

Meet Mary. She’s an average US citizen. 

Are you Mary? If not, congratulations – you’re not average! And neither is almost everyone else.

In the same way that buying size 9 shoes for every person in the population would leave most people unhappy and uncomfortable, a one-size-fits-all approach to nutrition is more like one-size-fits-almost-no-one. 

(Sorry, Mary)

What should you eat to be healthy?

In the US, healthy living guidelines focus on reducing the number of people suffering from health conditions linked to poor nutrition, such as diabetes and heart disease.

Every five years, the government issues guidelines that are designed to be easy to understand, simple to follow and applicable to a typical person.

At their most basic, the latest HHS/USDA guidelines recommend following a “healthy eating pattern” with an “appropriate calorie level”, including a variety of vegetables, fruits and whole grains, low-fat dairy, protein-rich foods and oils, and limiting saturated and trans fats, added sugars and salt.

Despite this good advice, something’s clearly not working.

More of us are very overweight than ever, 122 million of us have heart disease, and 100 million have diabetes or borderline diabetes.

Who designs nutritional guidelines?

The FDA bases its nutritional recommendations on scientific research, with a panel of experts systematically reviewing the latest studies every five years to create a report. This is then combined with feedback on previous guidelines to develop new ones.

This is a challenging task given that a single set of guidelines need to be produced, often using data from studies using average group results. 

Taking averages from research also leads to generalized headlines such as ‘cutting calorie intake by 300 calories can protect your heart’.

However, hidden within this data are participants who are ‘non-responders.’ In other words, people who reduce their food intake by 300 calories and find it has no effect on their health at all. Some people may buck the trend entirely and discover that cutting 300 calories from their nutrition plan actually has a negative impact on their health.

What’s more, nutritional research often focuses on people with specific health problems. For example, studies that measure the effect of salt on blood pressure tend to recruit people with high blood pressure. This is understandable, because decreasing the salt intake of healthy people with normal blood pressure is much harder to detect.

Research results in nutrition may seem to be contradictory, confusing or change in the light of new evidence. This may be because food is complex, the methods used to collect, analyze and interpret data vary from study to study, or simply because our bodies are complicated!

You’re unique. Your diet should be too.

There are healthy eating messages that should apply to everyone within the broad scope of current nutritional recommendations – such as eating more fibre, and more plant-based and fewer ultra-processed foods – but expecting one-size-fits-all average guidelines to fit you perfectly is overly simplistic.

What the ‘average person’ needs to eat may not be exactly the same as what you need to eat to stay healthy. Our responses to food are all different, and what works for one person isn’t necessarily the right choice for another.

The good news is that advances in nutritional monitoring, microbiome analysis and machine learning mean that we’re finally getting the data and the tools we need to truly measure, analyze and even predict responses to food on an individual level.

It’s not all in your genes

Our PREDICT study, which measured individual responses to food in more than 1,000 people in collaboration with Massachusetts General Hospital, Stanford University and King’s College London, shows how different we all are. Even identical twins – who share all their genes and much of their environment – have very different nutritional responses.

So although our genes do influence how our bodies break down and use food, their influence is limited: the first results from PREDICT showed that genetics explains less than 50% of the variation in nutritional responses between people.

Some of the differences are due to the particular blend of billions of bacteria living in our guts, known as the microbiome, while the rest are down to a complex mix of genetics, diet, activity, sleep, age and more.

Even so, whatever is responsible for the variation certainly isn’t random – we also found that individual people have regular, predictable responses to the same foods.

Find the foods your body loves

We’re now using the data from PREDICT to develop a home-based nutritional response test, combined with an app that will enable you to understand how your body works and choose the foods that best support your health.

We believe that there is no one right way to eat, and that good nutrition can’t be condensed into simple guidelines. The best way to stay healthy is to know your personal nutrition response and eat the way your body loves.

Sound interesting? Sign up to our early access mailing list to be the first to know how you can find the foods your body loves.

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