New data reveals how our diets are changing over time
We now know more than we ever have about what makes a good, balanced diet and the ways in which different nutrients impact our health.
Analysis of the burden of disease in England highlights the importance of a healthy diet and weight on risk of preventable diseases such as heart disease and some cancers.
The National Diet and Nutrition Survey has been running since 2008 and provides a crucial insight into how our dietary habits are changing over time.
The survey works by asking 1,000 people each year (500 adults and 500 children) about their dietary habits over a four-day period, with the sample designed to be representative of the UK population.
Blood and urine samples are taken to help us understand the level of different nutrients that people are consuming through what they eat and drink. The study is carried out by a consortium comprising NatCen Social Research and the National Institute of Health Research Cambridge Biomedical Research Centre.
It is the only survey in the UK to provide detailed information on food and nutrition intake within the population, with findings made available to researchers around the world.
Results are published every two to three years. Earlier this month we published the latest data from 2016/2017 to 2018/2019, giving us a snapshot of the state of the nation’s diet during this time.
Overall, there are positive signs that our diets may be becoming healthier, though there remain some concerning trends.
Eating too much sugar is a major cause of tooth decay and excess weight. While sugar consumption remains too high, since 2008 there has been a steady decline in sugar intake in both children and adults.
There isn’t a single factor at play here, but it is certainly in part thanks to a reduction in sugar sweetened soft drink consumption as people’s tastes have changed and as more manufacturers have offered low sugar alternatives.
This is an encouraging sign that government-led initiatives to reduce sugar intake are having a positive impact on our diets, and dovetails with our analysis of changes in the sugar levels of drinks, carried out as part of the sugar reduction programme.
However, further data shows that while consumption of sugary drinks has fallen, there has been no decline in sweet confectionery and chocolate consumption, with intake even going up in some groups.
While sugar consumption remains too high in both children and adults, the decreasing trend overall is encouraging.
There has also been a fall in red and processed meat consumption over the past decade, most likely for environmental and health reasons. Significantly, all adults now consume, on average, below the maximum recommended daily intake of red and processed meat (70g per day).
This is good news because we know that while red meat can form part of a healthy diet evidence indicates that eating too much can increase your risk of developing bowel cancer.
While there are positive signs that our dietary habits are changing for the better there do remain several concerning trends.
It is particularly concerning that saturated fat intake looks to be increasing in some groups, as this a major contributor to high cholesterol and therefore heart disease. SACN’s advice remains that saturated fats should be reduced to no more than about 10% of dietary energy.
While it is not possible to say definitively why this is happening, we do know there has been a big increase in popularity for lower-carb diets over recent years, many of which promote the consumption of higher-fat foods over those that are higher in wholegrain, starchy carbohydrate.
Average intakes of fibre, which is important for our digestive health, are still far below the recommended daily amount, with little sign of any meaningful change since 2008.
The latest data on salt intake for adults shows that average salt intake in 2020 was still higher (8.4g) than the recommended intake of 6g per day. While salt intake was been decreasing slowly over time, this decrease has slowed since 2014.
The latest NDNS also tells us that most people are still not eating the recommended 5 portions of fresh fruit and vegetables a day. Children aged 11 to 18 still only eat around 3 portions a day, though there has been a slight increase in consumption since 2014-16.
The data also gives us an understanding of lesser-known nutrient intakes that remain vital for our health.
One concerning trend is the steady decline in blood folate levels recorded by the survey since 2008, especially in women defined as being within childbearing age.
Having sufficient folic acid has been proven to significantly reduce the risks of the neural tube defect spina bifida occurring in pregnancy.
It is unclear why intake is declining but it is important that we try and reverse this trend. We know that food fortification can play an important role here: fortifying flour with folic acid is an effective and safe measure to reduce the number of pregnancies affected by neural tube defects. The Department of Health and Social Care have consulted on adding folic acid to flour and we support this.
The data also reminds us that most people do not get enough vitamin D, which is vital for bone and muscle health.
With many of us having been indoors more than usual this year, it’s especially important for everyone to take a daily vitamin D supplement containing 10 micrograms (400IU) as we go into the winter months, particularly vulnerable groups such as the elderly, those who don’t get outside and those with dark skin. Clinically vulnerable groups will be eligible for free vitamin D supplements throughout the winter period, starting in January.
While vitamin D plays an important role in our overall health, there is currently not enough evidence to support taking vitamin D solely to prevent or treat COVID-19.
Overall, the NDNS reminds us of the importance of promoting the benefits of a healthy, balanced diet as a foundation to good health.
While people’s diets may be improving in some areas, two thirds of the population remain overweight or are living with obesity and poor diets remain one of the leading causes of disease such as cancer, heart disease and type 2 diabetes. As we said in the summer, there is now stark evidence that living with obesity also increases the risk of severe COVID-19. This may also explain some of the inequities seen in COVID-19 risk across society.
There is no silver bullet to this challenge but encouraging and promoting healthier choices is of course a key factor. PHE is clear in its support for commitments set out by the Government to reduce the advertising and promotion of less healthy foods, to better support healthier choices.
We also are committed to continuing to monitor the nations diet and the progress of the food industry in their efforts on reducing sugar, salt and calories in every day products.
Avoiding excess calories and eating more fruit and vegetables, fibre and oily fish and less sugar, salt and saturated fat will help everyone lower their risk of long term health problems.