Winter days can really drag you down. Natural sunlight is a free and available mood enhancer. It encourages us to produce vitamin D and protects us from seasonal mood changes. However, because society is more aware than ever of skin cancer and sun damage, most of us have significantly reduced our exposure to natural sunlight. But, in doing so, we have traded the risk factors of one disease for others. Lack of natural sunlight can lead to vitamin D deficiency – which contributes to an increased risk of and Seasonal Affective Disorder (SAD).