One of the ways we are told to choose healthy foods is to read the label.
If you’ve left your glasses at home or if you don’t have time for the Nutrition Information Panel or the Ingredients List, a food manufacturer can include a Healthy Star Rating as an accessible, ‘good food’ indicator. The information panel and the ingredients list are often provided in the smallest font size possible on the back of the packet, while the Stars are a larger, colourful graphic on the front.
A star rating is displayed in ½ star increments, indicating which foods are better nutritional choices – the more stars displayed, the healthier the food.
A Star Rating is determined by the manufacturer using an algorithm (the Healthy Star Rating Calculator), based on the quantity of energy (kilojoules), saturated fat, total sugars, sodium, protein, dietary fibre, fruit, vegetables, nuts and legumes in the product.
The healthy Star Rating is not a legal requirement so a manufacturer can choose whether to use it or not. So you may not be surprised to learn that it is not included where the algorithm will give the food a low score.
Have a look at the Star Ratings given to these three products in the image below from Dr David Gillespie.
As you can see the algorithm has awarded a low rating to a product humans have been eating for thousands of years that contains cream, water and salt, and a high score to a product with a long list of ingredients including preservatives, hydrogenated vegetable oils and ‘natural butter flavour’. The ‘buttery blend’ and the ‘spread’ also have added nutrients, butter naturally has these and more.
Stars are used here for promotion rather than as a guide to healthy nutrition.
Out of date science
In Australia, the algorithm used to determine how many healthy stars a product gets is based on the Australian Dietary Guidelines. These guidelines, released in 2013, recommend avoiding saturated fat, added salt and added sugar.
Butter is more than 60% saturated fat and is often salted.
The reason that butter gets such a low star rating is that saturated fat has, in the past, been linked to heart disease. However, this evidence is equivocal.
A 2020 review of the latest science, (including a number of meta-analyses) by senior researchers from several institutions and published in the Journal of the American College of Cardiology concluded:
“Several foods relatively rich in SFAs (saturated fats), such as whole-fat dairy, dark chocolate, and unprocessed meat, are not associated with increased CVD (cardiovascular disease) or diabetes risk”.
This is a useful but not isolated study. Links to other evidence below suggest similar results. Healthy foods that deserve many stars are often foods that are least processed and closer to the foods that humans have always eaten.
The overall recommendation of this review is that:
“The long-standing bias against foods rich in saturated fats should be replaced with a view toward recommending diets consisting of healthy foods.”
Here is a similar evidence review that includes eight meta-analyses, focusing on dairy foods that concludes:
“…the current evidence supports the view that the full-fat dairy foods milk, yogurt, and cheese are nutrient rich and may be consumed without producing adverse effects on the cardiometabolic risk marker profile.”
This review found that their meta-analyses of both observational studies and RCTs did not suggest any harmful effects of full-fat dairy consumption on cardiometabolic disease and that much of the evidence used to inform dietary guidelines is of poor quality.
What sFED suggests
At best the current star rating is misleading and more about selling products than informing consumers about their dietary health
What we know is that the Australian Dietary Guidelines are currently under review with a revised version due in 2024. Despite the shortcomings highlighted here current Guidelines has some support. It also has some critics.
Let’s hope that the latest evidence is included in how the guidelines are revised.
The US recently updated their guidelines and they did not change significantly.
The issue here is that we are what we eat but what makes us healthy is not as profitable as many of the foods currently on supermarket shelves.
That’s a conundrum that market forces will not fix.