A new study has revealed that excessive sugar consumption may significantly increase the risk of developing gallstones in adults.
Researchers who analyzed data from the U.S. National Health and Nutrition Examination Survey (NHANES) between 2017 and 2023 found that every 100g per day increase in sugar consumption is associated with a 41% higher risk of developing the disease, even after accounting for factors such as age, sex, smoking, physical activity, and other chronic illnesses.
The study, published in the journal Scientific Reports, included data from 8,975 adult participants, excluding those under 20, pregnant women, and those with incomplete data.
The researchers relied on self-reports from participants to determine whether they suffered from gallstones or not, and estimated their daily sugar consumption through two separate 24-hour food reminder questionnaires.
The study showed that approximately 11.4% of participants reported having gallstones. Compared to those without gallstones, those with gallstones were typically older, had lower incomes, were more likely to be physically inactive, obese, or smoke, and had more chronic conditions. Women comprised the majority of participants (53%), and the incidence was higher among those who generally consumed fewer calories.
When participants were divided into four groups based on their sugar consumption, the group with the highest sugar intake had an 82% increased risk of developing gallstones compared to the group with the lowest intake. The third group had a 37% increased risk. The analysis also showed that the risk increased sharply as sugar consumption rose to approximately 150 grams per day, then stabilized slightly thereafter.
The researchers explain that high sugar consumption may promote the formation of gallstones through several biological mechanisms:
First: Sugar raises blood glucose and insulin levels, which increases the liver's production of cholesterol and its secretion into bile, leading to cholesterol hypersaturation of the bile.
Second: High-sugar diets may lead to insulin resistance and visceral obesity, which reduces gallbladder motility and causes bile stasis.
In addition, excessive sugar intake may stimulate oxidative stress and low-grade inflammation, impairing gallbladder function and accelerating the formation of cholesterol crystals.
It can also disrupt the bacterial balance in the intestines and the integrity of the intestinal wall, which indirectly contributes to the formation of stones.
The researchers used advanced machine learning techniques to improve the accuracy of predicting the risk of developing the disease. They developed a model based on XGBoost technology, and the model achieved a high accuracy rate of 89.6% in the test dataset.
The analysis showed that sugar consumption ranked sixth in terms of its impact on the risk of developing the disease, after age, gender, body mass index, and other factors.
These findings highlight that diet—specifically sugar consumption—is a modifiable risk factor, meaning it can be controlled and changed. Therefore, reducing sugar intake represents a potential preventative approach against gallstones. These changes are relatively simple to implement, can be applied at the population level, and are accessible to the general public.
These changes can also improve an individual's health while reducing the economic burden of gallstone complications, such as cholecystitis and pancreatitis, which significantly increase healthcare costs.
Despite the strength of the findings, the researchers acknowledge some limitations in their study. First, it is a cross-sectional study, meaning it measures the relationship at a single point in time and therefore cannot prove that sugar is the direct cause of gallstones (i.e., it does not establish a causal relationship). Second, the study relied on participants' self-reports of their gallstone history and sugar consumption, which may lead to inaccuracies in some of the results.
Therefore, researchers are calling for future long-term studies and further research to better understand the biological mechanisms and confirm these correlations before turning them into formal treatment recommendations.
