The World Health Organization, American Academy of Dermatology, and Skin Cancer Foundation recommend the following measures to prevent excessive UV exposure and skin cancer:
Limiting sun exposure between the hours of 10 am and 4 pm, when UV rays are the strongest
Seeking shade when UV rays are most intense
Wearing sun-protective clothing including a wide brim hat, sunglasses, and tightly-woven, loose-fitting clothing
Using sunscreen
Avoiding tanning beds and artificial UV exposure

UV intensity
The strength of sunlight is published in many locations as a UV Index. Sunlight is generally strongest when the sun is close to the highest point in the sky. Due to time zones and daylight saving time, this is not necessarily at 12 noon, but often one to two hours later. Seeking shade including using umbrellas and canopies can reduce the amount of UV exposure, but does not block all UV rays. The WHO recommends following the shadow rule: "Watch your shadow – Short shadow, seek shade!" Grapes
A 2022 study found that eating 60 grapes a day can stop you getting sunburn. Scientists found people who ate three-quarters of a punnet every day for two weeks were better protected against damage to the skin from ultraviolet light. Polyphenols found naturally in the fruits are thought to be responsible for the resistance. Sunscreen
Commercial preparations are available that block UV light, known as sunscreens or sunblocks. They have a sun protection factor (SPF) rating, based on the sunblocks ability to suppress sunburn: The higher the SPF rating, the lower the amount of direct DNA damage.
Mitochondrial myopathies are types of myopathies associated with mitochondrial disease. On biopsy, the muscle tissue of patients with these diseases usually demonstrate "ragged red" muscle fibers. These ragged-red fibers contain mild accumulations of glycogen and neutral lipids, and may show an increased reactivity for succinate dehydrogenase and a decreased reactivity for cytochrome c oxidase. Inheritance was believed to be maternal (non-Mendelian extranuclear). It is now known that certain nuclear DNA deletions can also cause mitochondrial myopathy such as the OPA1 gene deletion. There are several subcategories of mitochondrial myopathies. Signs and symptoms
Signs and symptoms include (for each of the following causes):

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like syndrome (MELAS)
Varying degrees of cognitive impairment and dementia
Lactic acidosis
Strokes
Transient ischemic attacks
Hearing loss
Weight loss
Myoclonic epilepsy and ragged-red fibers (MERRF)
Progressive myoclonic epilepsy
Clumps of diseased mitochondria accumulate in muscle fibers and appear as "ragged-red fibers" when muscle is stained with modified Gömöri trichrome stain
Short stature
Kearns–Sayre syndrome (KSS)
External ophthalmoplegia
Cardiac conduction defects
Sensorineural hearing loss
Chronic progressive external ophthalmoplegia (CPEO)
Progressive ophthalmoparesis
Symptomatic overlap with other mitochondrial myopathies

Cause
Zidovudine, an HIV medication can cause red ragged fiber myopathy. Diagnosis
Muscle biopsy: ragged red fibers in Gömöri trichrome stain. Treatment
Although no cure currently exists, there is hope in treatment for this class of hereditary diseases with the use of an embryonic mitochondrial transplant. References


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