Sugar makes the body acidic. Illness thrives in an acidic body. Also the stress and busyness of these "holidays" has a detrimental affect on the immune system. People are stressed, not getting enough sleep and eating unhealthy foods. This is a recipe for illness. Combine that with less sunlight ( less Vit D) and staying indoors, ( less fresh air) and being around more people who may be ill and you have " flu season." 😇