Last year (October 2016), a number of scientists pronounced that humans can not live longer than 115 years old.
This, despite the fact that a French woman, Jeanne Calment, died aged 122.
The problem arose because these scientists based their pronouncement on existing data, not factoring in the fact that we have never in the history of medicine applied ourselves to solving aging itself, but rather to solving the health issues that arise as side effects of aging.
This is similar in a way to stating that the highest point a person could ever touch on a wall is about 2.5 meters above ground, totally ignoring that we can invent stools or ladders.
Aging is only recently being recognised as a disease, and the fundamental causes of it are still being identified.
One reason we have an apparent limit on longevity is that genes have a “half-life” of sorts, where they can only divide a certain maximum number of times before they refuse to divide anymore. This limit is called the “Hayflick limit” after the person who noticed it.
The reason that genes won’t divide forever is that the ends of them, the telomeres, get shorter each time a division happens, and eventually they are so short that another division might cause a loss of functional code, so the cells notice this and refuse to divide anymore, going into senescence mode.
There are two treatments which can solve this issue.
Firstly, there is a treatment which has been demonstrated to lengthen the telomeres. If this treatment is repeated each ten-fifteen years, the telomeres should stay long indefinitely.
Second, you can kill the already-senescent cells by blocking the FOXO4 protein using a FOXO4-DRI (a FOXO4 peptide whose amino acid sequence has been reversed). This allows the senescent cells to die off, letting the body replace them with fresher cells.
And to help the DNA replicate more correctly, probably reducing the frequency that telomere treatment would be needed, you can increase the NAD+ in your cells by using NMN supplements.
People in the past never had access to those treatments, so it is understandable that there was an apparent limit to lifespan, but there really is no excuse – a scientist should never make an absolute claim like that which can so easily be shown to be false.