Foods that don’t meet the standard for a clean diet are not necessarily “dirty” or harmful to consume.
Research has not yet found that the nature of a food being artificial in of itself makes the food unhealthy. For example, some healthy protein bars include artificial ingredients but can be healthy for us if they are nutrient-dense options. However a majority of artificial ingredients and highly processed foods have unhealthy properties - they are often very high in calories, saturated fats, and added sugar without providing much nutritional value. Too much added sugar and fat can have a serious impact on your diet and certain health conditions when consumed in excess.
And while some processed foods can provide good nutrition, a growing body of evidence continues to suggest that the quality of your food choices is an important factor in overall health, longevity, and weight loss.