Anyone who has had a manicure knows that it is more profitable to do it on the toenails, because it lasts much longer than on the hands. The reason, basically, is that the growth is not the same. Fingernails grow faster, so the unpainted area would start to show much earlier. But why is that?
For a long time this was a mystery. In fact, there are now some well-established theories, although it is not clear whether other phenomena are involved.
Broadly speaking, the reason for the heterogeneous growth lies in the fact that we put our toenails to much less use. Especially in winter, when they are well protected, with closed shoes and socks or stockings. Our fingernails, on the other hand, spend the day in use, typing on a computer, crawling across touch screens, clutching a scouring pad to wash the dishes… Although we don’t stop to think about it, we make a lot of use of them. And that’s the main reason why we have to cut them so often. Of course, there could also be some other cause involved.
Nails are structures that are part of the skin, although they are mostly made up of dead cells hardened with keratin. This is a fibrous protein that is also found in other animal structures such as horns or feathers.
It has several known functions, the most obvious of which is protection. However, it also has other less intuitive applications, such as improving the precision of finger movements by exerting counter-pressure on the digital pulp.
It is known that toenails grow at a rate of 1.6 millimeters per month, while fingernails grow more than twice as fast, at 3.5 millimeters per month. As for the recovery of a complete nail, it takes between 6 and 9 months.
However, it should be noted that this is the average and that, in reality, such growth will depend on factors such as age, gender, genetics and a person’s health. Nutrition is also very important. In fact, many nail problems are associated with nutritional imbalances.
What is needed for nail growth?
Although we think of nails as dead, precisely because they are composed of dead cells, oxygen and a good supply of nutrients are needed for them to grow beyond the epithelium.
In fact, we have already seen that nutrition is very important for them to grow properly. Vitamin B7, also known as biotin, is one of the nutrients that are so necessary for nail growth. This is precisely why many people take it in supplements to alleviate the problem of brittle nails.
Now, let’s say we have a healthy person, with proper nutrition and no genetic component affecting the growth of their nails. What is it that causes toenails to grow much more slowly?
The keys to slow toenail growth
One of the first people to study toenail and fingernail growth was Dr. William Bean of Walter Reed Army Medical Center in Washington.
His research on this neglected structure of our body was remarkable because he spent 35 years observing his own. Thus he not only came to obtain the average data on how long nails grow in a month. He also observed a slowdown with age as he got older. He published his results in 1980.
Later, dermatologist Rodney Dawber conducted his own experiment aimed at finding out what are the keys behind the growth of fingernails and toenails.
Previous studies had led him to the intuition that nails grow longer as they get more use. So he made the best of an injury to his ring finger during a rugby match, because he thought that, by having it immobilized, that particular nail would grow more slowly. And so it did, because in that period it grew 25% slower than the rest.
This all made sense. Until then it was believed that there are two reasons why toenails grow more slowly. The first is that, being farther away from the heart, they have a reduced blood flow, especially when it is colder. This prevents a good supply of oxygen and nutrients for optimal growth. On the other hand, it could be that it is the continuous stimulation of the nail that also helps it to grow. In fact, this stimulation also promotes blood circulation.
Toenails are usually wrapped in shoes and socks. And quite still. However, our fingers and toes are constantly rubbing and moving. This would also explain why the nails on the longer fingers, which we use the most, grow faster. Or why toenails grow a little faster in summer, when it’s cooler, blood flow is better and it’s also more common to wear open-toed shoes and have some rubbing on the tips of our toes.
So that’s why a foot manicure is much more cost-effective. Of course, none of them last forever. As long as we are alive, our nails, to a greater or lesser extent, will continue to grow. Once we are dead, they do not; because, in fact, it is a myth that the nails of the dead continue to grow. What happens is that the surrounding tissues retract and that gives them a longer appearance. But, once there is no more blood flow, the nail has nothing to do.