It is recommended to focus on maintaining a healthy lifestyle by consuming plenty of fruits and vegetables, following a Mediterranean diet, engaging in moderate-intensity exercise for at least 150 minutes per week, managing stress effectively, and getting adequate rest (a minimum of 6 hours of sleep per night). Depending on your diet, it may be beneficial to consider taking a vitamin D supplement to ensure you are meeting your daily intake recommendations. The suggested daily intake of vitamin D for individuals living in Nordic countries is 400 to 800 international units per day. If you have any further questions, feel free to ask for more guidance.