Aim to get 10-30 minutes of midday sunlight to maintain healthy blood levels. Also, it’s important to know that people with darker skin may need a little more than this.
So, factors that can affect your ability to produce vitamin D from sunlight include your skin color, the time of day, how much skin you expose to sunlight and whether you are wearing sunscreen.
It’s best to apply sunscreen after 10–30 minutes of unprotected sun exposure to help prevent sunburn and skin cancer.