Taiwanese nephrologist warns of risks from ‘natural’ remedies for diabetes and kidney disease

A case in Taiwan highlights the dangers of relying solely on ‘natural’ remedies like bitter gourd juice for blood sugar management in people with kidney impairment, underscoring the importance of medical treatment and dietary caution.

A nephrologist in Taiwan is warning that “natural” remedies can still be risky for people with diabetes and kidney disease, after a 60-year-old man with stage 3 chronic kidney disease was sent to hospital with dangerously high potassium levels following heavy consumption of bitter gourd juice. Hong Yongxiang, director of Hong Yongxiang Clinic, said the patient’s glycated haemoglobin had reached 9.2% as he searched online for ways to lower blood sugar without relying on prescribed medicine. Doctors say the case is a reminder that diet can support glucose control, but it cannot replace medical treatment.

Hong said the mistake was not choosing one healthy food but treating it as a cure-all. That point is consistent with broader nutrition guidance, which generally recommends combining blood-sugar-friendly foods as part of an overall eating plan rather than depending on a single ingredient. Healthline and Medical News Today both note that foods such as oats, nuts, legumes, vegetables and other high-fibre options may help reduce glucose spikes when they are used in balanced meals.

In his ranking of foods with the best evidence for helping control blood sugar, Hong placed non-starchy vegetables and fibre-rich foods at the top, followed by extra-virgin olive oil and nuts, cinnamon, oats and bitter gourd. He said vegetables such as broccoli and spinach can slow the entry of glucose into the bloodstream, while olive oil and nuts may improve insulin resistance because they contain monounsaturated fats and polyphenols. Healthline also highlights broccoli, nuts and other high-fibre foods for glucose management, while its review of cinnamon says the spice may modestly affect blood sugar, although results vary.

Hong also urged caution for people with kidney disease. Bitter gourd, spinach and other potassium-rich foods may need extra care in later-stage chronic kidney disease, and he advised blanching some vegetables first to reduce potassium content. He warned that bitter gourd should never be consumed in large amounts as juice, especially by patients whose kidneys are already impaired. That caution matters because kidney patients often have less ability to clear potassium, making dietary excess potentially dangerous even when the food itself is considered healthy.