Eating too many natural foods to control blood sugar can harm kidneys, doctor warns

Consuming excessive amounts of natural foods to manage blood sugar levels can inadvertently harm the kidneys, according to Dr. Hong Yong-xiang, director of Hong Yong-xiang Clinic. He shared the case of a 60-year-old man with stage 3 chronic kidney disease and diabetes who, fearing side effects from Western medicine, drank large quantities of bitter melon juice daily. This practice not only failed to stabilize his blood sugar, which reached a high of 9.2% glycated hemoglobin, but also led to dangerously high potassium levels, requiring emergency treatment.

Dr. Hong emphasized that dietary changes can only assist in blood sugar regulation and cannot replace medication. He highlighted the importance of correct selection, combination, and preparation of foods, rather than simply consuming large quantities of a single item. He identified five natural foods scientifically validated for their blood sugar-lowering properties, along with crucial consumption guidelines to prevent kidney damage.

The top five blood sugar-lowering foods include bitter melon (ranked fifth), which contains compounds similar to insulin but is high in potassium and should be blanched to reduce potassium for those with advanced kidney disease. Oats (fourth) are beneficial due to their soluble fiber, but consumers should choose whole, unprocessed varieties. Cinnamon (third) can significantly lower fasting blood sugar, but excessive intake may affect liver and kidney function due to coumarin content. Extra virgin olive oil and nuts (second) are rich in healthy fats and polyphenols that improve insulin resistance, but their high calorie content requires careful portion control as part of a weight management strategy for kidney health.

Non-starchy vegetables and dietary fiber (ranked first) are highly effective in slowing glucose absorption and reducing blood sugar spikes. However, individuals with late-stage kidney disease should still be mindful of potassium content and blanch these vegetables before consumption. Dr. Hong stressed that the key is balanced integration into the diet, not overconsumption, to effectively manage blood sugar and protect kidney function.