This means that most of the vitamin Tonaki Tinnitus Protocol has to be obtained from sunlight or supplements if you live in a cold place, which rarely gets very hot. Here are some tips to keep in mind regarding vitamin D: If you use sunscreen, you will not make much, if any, vitamin D. If you live in the US, draw a line from San Francisco to Richmond. If you live north of this line, the sun's rays are too weak to trigger vitamin D production, except during the summer. According to Cancer Council Australia it is only when the UV index is greater than 3 that the necessary UVB wavelengths are present in sufficient quantities to produce vitamin D. Clear-skinned people from northern areas highly evolved to use sun more efficiently. If you have dark skin, you will need even more exposure to the sun to keep your vitamin D levels up. Tonaki Tinnitus Protocol: Is it Effective or Not? Read Review Before Buy | Free Supplemen Trial