The analysis of the Diabetes dataset has revealed the following issue:

```json
{
    "issue": "Substantial number of '0' values in SkinThickness column",
    "evidence": "SkinThickness column contains 227 '0' values out of 768 total entries",
    "description": "The SkinThickness column of the Diabetes_dataset.csv is supposed to capture skin fold thickness, which is a significant measurement in diagnosing Diabetes Mellitus. However, 227 out of 768 entries (approximately 29.6% of the data) are recorded as '0', which is implausible for skin thickness measurements and suggests missing or incorrectly recorded data. This high proportion of '0' values could potentially bias any analysis or machine learning models developed using this dataset. It indicates a need for data cleaning or imputation strategies to address these missing or implausibly recorded values."
}
```