Miss Widdecombe, who was promoted to the health brief by William Hague last week, said in a radio interview that the two-parent heterosexual family should remain society's "preferred model".
Asked if she agreed with the former Secretary of State for Defence, Michael Portillo, that the Tory party should open its arms to gays and single mothers, she told BBC Radio 4's The Westminster Hour: "I certainly don't think that those sorts of lifestyle have equal validity with that of the traditional family.
"That is not to say that they should not be tolerated. I don't think you can allow every lifestyle - just because you tolerate it - equal validity with what should be a preferred model. No substitute has ever been found for the traditional family"
Miss Widdecombe, a convert to Catholicism, also restated her opposition to abortion.
Asked if she would be comfortable being responsible for the administration of abortions as a potential future health secretary, she replied: "But just a minute, I am not the health secretary, I am the shadow health secretary.
"Indeed you are right, I would never license an abortion clinic but that is not a problem I face.
"I think it is very serious when we actually have abortions done just because the babies will be ugly, when we have babies routinely aborted for hair lip or club foot. I think that is a very, very sad reflection on society."
In a newspaper article last month, she wrote: "One of the sundry horrors for which this Government is likely to be remembered will be that it gave its imprimatur to sodomy at 16."
The House of Commons is expected to vote later this month to lower the age of consent for gay men to 16.
"They will clothe the whole revolting business with the politically correct jargon of equal rights and the need to respect the sexual orientation of the individual," Miss Widdecombe wrote.
A Labour Party spokeswoman seized on Miss Widdecombe's remarks.
In a reference to Mr Portillo's efforts to argue the case for a more caring image for the party, she noted: "In October Michael Portillo said the Tories had suffered in government from a reputation of being too intolerant. Ann Widdecombe's comments today show they have learned absolutely nothing.
"Why have we grown afraid of protecting our children? At 16, the law says a person is too young to drive a car or buy an alcoholic drink. Are we really going to say that buggery is OK but beer isn't?"Reuse content