In ancient China, as in many early civilizations, there were various health issues related to food and diet. The Chinese had a long history of culinary sophistication and were aware of many aspects of diet and health, but they still faced challenges common to pre-modern societies. Here are some of the key food-related problems and diseases that were likely present in ancient China:

1. Food Poisoning and Contamination: Like other ancient cultures, the Chinese would have dealt with foodborne illnesses caused by bacteria, viruses, and parasites due to improper food handling, preservation, or cooking methods. Meat, fish, and even grains could become sources of contamination.

2. Parasitic Infections: Consumption of undercooked or raw food could lead to parasitic infections. Tapeworms, roundworms, and other parasites were common issues in ancient societies, including China.

3. Nutritional Deficiencies: Despite the diverse range of ingredients in Chinese cuisine, certain segments of the population, particularly the poor, might have suffered from nutritional deficiencies due to limited access to a wide variety of foods. Deficiencies in vitamins and minerals could lead to conditions such as scurvy (vitamin C deficiency) or beriberi (thiamine deficiency).

4. Diet-Related Chronic Conditions: The diet of the wealthier classes in ancient China, which could be rich in meats and oils, might have led to diet-related chronic conditions like obesity, diabetes, and heart disease, much like in other ancient civilizations.

5. Adulteration and Toxicity: The adulteration of food with non-food materials to extend quantity or enhance appearance was a potential risk. Moreover, the use of certain herbs and preparations in traditional medicine or cooking, without a full understanding of their effects, could lead to toxicity.

6. Alcohol Consumption: While not as prominent as in some other ancient cultures, excessive alcohol consumption (mostly rice wine) could lead to health issues, including liver disease and alcoholism.

7. Famine and Starvation: As in other ancient empires, China experienced periods of famine due to natural disasters (like droughts and floods), war, or poor governance. Famine could lead to widespread malnutrition and starvation, exacerbating all other health problems.

8. Unsanitary Food Practices: Hygiene standards in ancient times were not what they are today. Unsanitary practices in the handling, preparation, and storage of food could lead to contamination and outbreaks of foodborne illnesses.

9. Dysentery and Waterborne Diseases: Contaminated water sources could lead to diseases like dysentery, especially in densely populated areas or during military campaigns.

Ancient Chinese medical texts, like the "Huangdi Neijing" (The Yellow Emperor's Classic of Medicine), do show an understanding of the relationship between diet and health, and dietary therapy was an important aspect of traditional Chinese medicine. However, the limitations in scientific knowledge about microbiology and nutrition meant that food- and waterborne diseases were still significant challenges.