Very low-calorie ketogenic diet (VLCKD)

This diet favors animal and/or plant-based sources of dietary fibre, protein, monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and saturated fatty acids (SAT) (e.g., non-starchy vegetables, chicken, lamb, beef, eggs, cream, cheese, butter, olive oil)
Nall 2018 Medical News Today.

The Very low-calorie ketogenic diet (VLCKD) is characterized by a high proportion of fat (70%), adequate protein (20%), and a low proportion of carbohydrates (CHO—10%, <50 g per day)
Shilpa & Mohan 2018 Indian J. Med. Res. 148: 251–253

see also:
Inflammatory Bowel Disease (IBD) & Short-Chain Fatty Acids (SCFAs)
Ketosis…