Added Sugar: What Counts and How Much Is Too Much

Halloween ends, in a lot of homes, with a pile of sweets on the kitchen table and some negotiation about how many can be eaten before bed. We’re not going to argue for confiscating the bag. A few days of sweets in late October makes up a small part of a year’s sugar.

The studies on sugar and health are about the everyday kind, and much of that doesn’t announce itself. It’s in breakfast cereals and pasta sauces, and for a lot of people a good share of it comes in a glass.

What Counts as Free Sugar

Health guidelines talk about free sugars, and the definition is more useful than it sounds. Free sugars are the ones added to food and drink by a manufacturer, a cook or you, plus the sugar that occurs naturally in honey, syrups and fruit juice. The sugar inside whole fruit, vegetables and plain milk doesn’t count. So an orange isn’t a source of free sugar, but a glass of orange juice is, and a spoonful of honey counts the same as a spoonful of table sugar.

In 2015 the World Health Organization recommended keeping free sugars below 10% of daily energy, and rated that a strong recommendation. For someone eating about 2,000 kcal a day, that’s around 50 g. It also suggested going further, below 5%, which for an adult is about 25 g or roughly six teaspoons, but made that one conditional because the evidence behind it was weaker.

World Health Organization (2015). “Guideline: Sugars intake for adults and children.” Geneva: World Health Organization.

Weight and Teeth

A 2013 review in the BMJ gathered the randomized trials and cohort studies on sugar and body weight. In the trials, people who cut back on free sugars lost a little weight and people who ate more gained a little, less than a kilogram on average either way. The more telling trials swapped sugar for other carbohydrates and kept calories the same. In those, weight didn’t change. Sugar’s effect on weight seems to run through the extra calories it adds, which are easy to take in without noticing.

Te Morenga, L., Mallard, S. & Mann, J. (2013). “Dietary sugars and body weight: systematic review and meta-analyses of randomised controlled trials and cohort studies.” BMJ, 346, e7492.

Teeth were a large part of why the WHO set its numbers where it did. A systematic review written to inform the guideline found less tooth decay where free sugars stayed below 10% of energy, and signs that it was lower still below 5%, though the evidence for the lower figure was thinner. Dentists also care about how often teeth meet sugar, not only how much, which is a fair argument for eating the sweets after dinner instead of one every half hour all afternoon.

Moynihan, P.J. & Kelly, S.A.M. (2014). “Effect on caries of restricting sugars intake: systematic review to inform WHO guidelines.” Journal of Dental Research, 93(1), 8-18.

Why Drinks Come First

Sugar in liquid form adds up fast. A standard 330 ml can of cola holds about 35 g, already more than the WHO’s lower figure for a whole day, and in the US sweetened drinks are the largest single source of added sugar in the diet. Juice, sweetened iced tea, energy drinks and the bigger flavored coffees work the same way, and they go down in minutes.

One of the longest looks at drinks and survival comes from two large US cohorts of nurses and other health professionals: about 118,000 adults, followed for roughly three decades. People who drank more sugar-sweetened drinks had higher mortality over that time, mostly from cardiovascular disease. Swapping one sugary drink a day for a diet version was linked to slightly lower risk, although very high intakes of diet drinks were themselves linked to higher mortality in women, and the authors’ own advice was to replace sugary drinks with other drinks, preferably water. All of this is observational, and heavy soda drinkers probably differed from everyone else in ways the authors couldn’t fully adjust for.

Malik, V.S. et al. (2019). “Long-Term Consumption of Sugar-Sweetened and Artificially Sweetened Beverages and Risk of Mortality in US Adults.” Circulation, 139(18), 2113-2125.

Labels, Treats and the Rest of the Year

If you want to cut back, start with the glass. Someone who drinks a can of cola every day and switches it for water or unsweetened tea removes about 35 g of free sugar a day without changing a single meal. After that, sweets and cake are easier to keep in proportion when you eat them on purpose, as a treat, rather than out of a bag on the desk.

On packaged food, compare sugars per 100 g rather than per serving, because serving sizes vary between brands. In the UK, more than 22.5 g per 100 g counts as high and 5 g or less as low. European labels list total sugars, which include the natural sugar in milk and fruit, so plain yogurt shows some sugar with none added. US labels now give added sugars a line of their own.

To see where your own sugar comes from, log what you eat and drink in Lamplit for a week, and give the sweet drinks their own entries. A typed description gets an AI calorie estimate. For packaged food, scanning the barcode is free and shows the Nutri-Score when Open Food Facts has it (sugar is one of the things that score counts against), along with the NOVA processing group and any additives listed. At the end of the week, look at how many of your entries were drinks.

Log today’s meals and drinks in Lamplit, sweet ones included. It’s free.