The news anchor confirmed her departure from the NBC morning show in May after "months of personal reflection and private conversations between [her] family and friends".
While it was suggested that her decision was based on the desire to care for her husband Richard Cohen, who suffers from multiple sclerosis, Vieira has insisted that Cohen is currently well and that the pair want to take advantage of his relatively good health.
"It was being distorted, because it looked better to make it, 'Poor Meredith, she triumphs through it all', but that wasn't the case," she explained to People.
"We don't know from day to day what might happen. So why not enjoy life now? It's very precious, and anyone living with any kind of illness knows that. Health is fleeting, and you need to celebrate it while you still have it."
Vieira's Today spot will be filled by colleague Ann Curry, while Natalie Morales will take over regular news reading duties and NBC News White House Correspondent and MSNBC anchor Savannah Guthrie will co-host the programme's third hour.