The study published in August 2023 looked at the association of added sugars and kidney stones in U.S. adults. The researchers found that those who consumed ≥25% of their daily calories from added sugars had an 88% higher chance of kidney stones compared to those sitting at 5%.¹

Added sugars are sugars put in foods during preparation or procession, rather than occurring naturally in foods. The CDC provides the following examples of added sugars to watch out for:

Brown sugar, cane juice, corn syrup, dextrose, fructose, fruit nectars, glucose, high-fructose corn syrup, honey, lactose, malt syrup, maltose, maple syrup, molasses, raw sugar, and sucrose.²

Higher consumption of added sugars has well established associations to a range of negative health effects including but not limited to weight gain, high blood pressure, inflammation, diabetes, fatty liver disease. Many of these health effects are risk factors for kidney stone formation.

Added sugars can also lead to an increase in the amount of calcium in urine and less urine volume, increasing the risk of kidney stones forming. Sugar can also raise the acid level of your urine creating a more favorable environment for kidney stone formation.

The World Health Organization (WHO) recommends adults and children reduce their daily added sugar intake to less than 10% of their total daily energy intake.³

Sugar hides in many of the processed foods we eat every day. So, it can be very easy to unintentionally go over the 10% recommendation. Here are some simple foods to avoid or be mindful of when trying to make some easy reductions in your sugar intake:

• Avoid sugary drinks such as fizzy drinks, juice, cordials, and syrups,
• avoid fruit juices and eat your fruit instead,
• be aware of processed breakfast cereals high in sugar,
• choose unsweetened yoghurts and add fruit rather than store bought flavoured yoghurts,
• have a few squares of dark chocolate to satisfy your sweet tooth after dinner instead of larger desserts.

1. Yin S, Yang Z, Zhu P, Du Z, Yu X, Tang T, Borné Y. Association between added sugars and kidney stones in U.S. adults: data from National Health and Nutrition Examination Survey 2007-2018. Front Nutr. 2023 Aug 4;10:1226082. doi: 10.3389/fnut.2023.1226082. PMID: 37599678; PMCID: PMC10436224.
2. CDC Know Your Limit For Added Sugars
3. World Health Organisation, WHO calls on countries to reduce sugars intake among adults and children
4. Healthify NZ, Sugar – how to cut it down