Venus Williams was forced to make drastic change to diet after being diagnosed with rare incurable disease

Seven-time tennis major winner Venus Williams reportedly changed her diet to combat an incurable disease - and the switch influenced her sister Serena.

Venus, 44, is the elder of the Williams sisters, with Serena, 43, being just over a year younger.

Between them, they have 48 Grand Slam titles - 23 singles for Serena, seven singles for Venus, 14 doubles for both, and four mixed doubles for Serena – and are widely considered to be two of the best tennis players of all time.

However, in 2011, Venus learned of an incurable autoimmune condition called Sjögren’s syndrome - something she admitted was hard to accept.

"I hadn’t felt myself for a while," Venus told Harpers Bazaar in September 2024.

"But at the same time, it was hard to accept. I’m used to doing whatever I want, working hard and staying fit. To realise that it’s not something you can work through, that this is your life now... that was hard.”

The condition is described as “a condition where the glands that produce fluid, such as tears and spit (saliva), stop working properly. It can affect your daily life, but treatments can help ease the symptoms,” according to the NHS.

Symptoms include aching muscles and extreme tiredness, which isn’t ideal for a top-level sportsperson.

Her sister, Serena, suggested that she and her big sister attend a retreat to see if they could make lifestyle changes to help manage the condition.

Venus became vegetarian and completely changed her nutrition as a result, and now reportedly follows a sugar-free diet to help alleviate exhaustion and explained how the condition is now manageable.

Venus and Serena Williams (Credit:Getty)

Serena also explained how she changed her lifestyle because of her sister’s diagnosis when speaking to Sports Illustrated in 2014.

"It all started because I didn't want to bring bad food into the house,” Serena said. "I live with my sister, Venus, who has Sjögren's syndrome, an autoimmune disease."

Speaking to Bonappetit in 2013, the younger of the pair revealed that she had been “eating a lot healthier for her sister”.

“For me, ‘green’ used to mean ‘yuck,’” Serena said. “But I've incorporated a lot of raw things in my diet this year. Venus calls us "chegan"—because we cheat with a little bit of fish and chicken.”