Chris Kamara said he is suffering from apraxia of speech after sparking concern with an appearance on Soccer Saturday.
The former player, who had spells at Leeds United, Sheffield United, and Bradford City, appeared to slur his words while on screen this weekend, prompting viewers to message him on social media.
The 64-year-old said on Twitter he has developed the speech disorder alongside an existing thyroid issue.
He wrote: "Just wanted to let a few of you know who tweeted me today that I am ok ish. Alongside my Thyroid problem I have developed Apraxia of Speech & have been working to get my speech back to normal."
He added: "Some days it can be a little slow and some days it's normal. Hopefully I can beat this!"
Messages of support soon flooded in.
Kamara's Soccer Saturday co-presenter Jeff Stelling replied: "You still bring life, energy, fun and understanding to all your reports on Soccer Saturday. We all love you pal. Keep going!"
Olympic gold medallist hockey player Sam Quek and former footballer Viv Anderson were also among those sending messages of support.
Kamara previously underwent a brain scan to check if he was developing dementia after suffering from what he described as "brain fog".
He worried the illness might be related to heading the ball as a footballer, however, his symptoms were instead explained by an underactive thyroid, for which he now receives treatment.