Whole grain consumption and risk of cardiovascular disease, cancer, and all cause and cause specific mortality: systematic review and dose-response meta-analysis of prospective studies

What about gluten-free diets in coeliac disease and Bariatric surgery and strict diets for weight loss? Do they also suffer from various diseases (like cardiovascular diseases, cancer, diabetes, etc) those get lowered by taking whole grains. The article is not complete without making a mention of these particular categories. Or else, research should be undertaken for these categories of people.