Rachel Riley, 33, regularly battles with trolls on Twitter for her criticisms of the Labour party and leader Jeremy Corbyn amid the ongoing anti-Semitism row.
Now the Countdown star has said the abuse online towards her has worsened and includes physical threats.
She told The Times newspaper: “The more I speak, the more abuse I get, and the more abuse I get, the more I speak.
“It’s got to the point where I can’t look at my Twitter feed any more … it’s just a constant stream.”
Rachel, who is Jewish, revealed it’s even affecting her job and will have added protection on the set of Countdown.
She added: “We are getting more security for Countdown.”
Rachel, who is in a relationship with Strictly Come Dancing professional Pasha Kovalev, said she believes she is a “target” for speaking up against anti-Semitism, and that she does not “take it lightly”.
She said: “With the hashtag Get The Tories Out or the red rose or hashtag JC4PM, they say to me ‘You’re only calling out the left’.
“Well, I’ve been attacked by people on the left and the best way to not have me talk about anti-Semitism on the left is not to be anti-Semitic.”
Rachel has previously stated she has no political allegiance but told the publication she would not vote for Labour now.
The mathematician said she believes the party is “actively encouraging the abuse of people who are standing up to this”.
Jeremy Corbyn has strongly denied allegations of anti-Semitism during the controversy that has ripped through his party.
Earlier this week, Rachel made a speech at the House of Commons to speak about anti-Semitism at the Holocaust Memorial Day.
Before heading off, the star uploaded a selfie of her and her boyfriend Pasha as she prepared for the night.
She wrote beside the snap: “Off to the Houses of Parliament with my moral support for my speech at tonight’s @HolocaustUK event.”
Rachel followed the post up with a picture of herself making the speech and thanked everyone for listening.
“The speech I just delivered at @HolocaustUK’s event,” she said.
“Important #WeRemember and learn from the mistakes of the past, huge thanks to everyone who continues to spread this message. #BeLouder against antisemitism.
Rachel added in a separate tweet: “My speech is dedicated with love to all the victims and survivors of the Holocaust, and all the modern-day backchannel mensches. You know who you are.”
Countdown airs weekdays on Channel 4 at 2.10pm.