Every-other-day fasting can protect the eye from glaucomatous damage – in a process completely different to intraocular pressure (IOP) maintenance, Japanese scientists have discovered.
The Tokyo Metropolitan Institute of Medical Science team found that a group of mice on the diet suffered less photoreceptor and retinal degeneration from the disease than a group eating normally.
Calorie restriction is already known to provide some protection against the effects of injury and disease. In the study published in the journal Scientific Reports, the diet alleviated the visual impairment of the mice with normal tension glaucoma.
In a key finding, the two groups of mice did not differ significantly in their IOP measurements, which demonstrated that the protective effect of the diet involved a different ocular mechanism.
The researchers found boosted levels of molecules that support the growth and survival of nerve cells in the eyes of the mice on the fasting diet.
In the paper, the team emphasised that: “Our findings raise interesting possibilities that every-other-day-fasting is beneficial for glaucoma patients.”
Because the mice had significantly increased levels of β-hydroxybutyrate in their bloodstream, the researchers explained that methods to boost this molecule could give similar retinal protection. However, the Japanese scientists believed that calorie restriction protected the photoreceptors of the mice in a number of different ways.
They also hypothesised that: “Some caloric restriction mimetics such as resveratrol [a compound found in red wine and chocolate] and sulforaphane [found in broccoli] might have similar benefits on neuroprotection.”