According to your description of the toenail problem, and the details of your picture. Generally it may be thought to be due to malnutrition, lack of nutrition, including the calcium deficiency aspect. It may also not be keeping up, which is also a kind of dietary aspects out of some problems. During this period of time, you can also eat a little bit more nutritious food, such as like fish and bone broth food eat more, as well as fresh vegetables and fruits, as well as some milk and so on to drink a little bit more. There is also a possibility that this period of time has not suffered some collision and so on, you may not pay attention to, so this period of time may find some toenails have some problems, this aspect do not have to go to tension, may be after a period of time will slowly disappear. There is also the last situation, is because of their shoes, usually walking is not a little bit of foot pressure, which is also the most likely to appear toenails have some cracked vertical lines, this aspect is also and their own overwork also have some reasons. In addition to this, may be because and their gray nail aspect also has some relationship, so also will appear similar situation. During this period of time, it is best to look at the color of their toenails have not carried out some changes, if the color has begun to darken, then it may be the possibility of grey toenails are more, this time it is necessary to go earlier to carry out the corresponding solution, so that their toenails will not aggravate the situation. There is also a situation is this period of time they may have some fatigue and a situation similar to the above, is the toenail nutritional deficiencies, this period of time you can maintain a good enough sleep. Do appropriate exercise, usually after a period of time will be effective recovery. Do not be too nervous, keep a good balance in your mind, do not have some anxiety. This time pay more attention. The first to keep up with the nutrition, and then usually still have a good habit of their own work and rest. Try not to stay up late, pay more attention to rest. Then after a period of time to see if you have these conditions. In general, about three months later, there will be very few similar situations. Or there has been some improvement. If more than this time, they still try to pay more attention to it, it is best to check.