Ms Smith said she "felt sorry" about claiming expenses for films
Home Secretary Jacqui Smith has defended her use of MPs' allowances as "fair and reasonable".
She has been criticised for listing the house she shares with her sister as her main residence, while claiming second home expenses for her family house.
She told BBC Radio 4's Today programme it was the "nature of the job" that MPs had to furnish and run two properties.
But Ms Smith added she felt "sorry" and "angry" that she had claimed expenses for adult films watched by her husband.
The growing number of revelations about MPs' expenses has led to calls for the rules to be tightened.
Ms Smith has apologised for "mistakenly" claiming £10 for pornographic films her husband watched, and is being investigated after claiming at least £116,000 for her constituency house.
She had designated her sister's London house, where she rents a room, as her "main" home.
Ms Smith told Today: "When I became an MP, my husband and I had to make a decision knowing I would spend more time in London."
She added that she and her sister shared the costs of running the London home, adding: "I'm not in some box room in the top of the house."
Ms Smith also said: "What I claim is what I think are fair and reasonable expenses for that fact I have to live in two houses... it's the nature of the job of being an MP that they have to live in two houses."
She added: "The priority for me is not to let that [controversy] distract me from my job as home secretary and MP for Redditch."
Ms Smith's remarks follow leaks of expenses details at the weekend, which suggested she had bought a barbecue, patio heater and toothbrush holder with taxpayer funds.
She was asked on GMTV whether it was fair for tax payers to fund the cost of a flat screen TV, scatter cushions at her Redditch home, a toothbrush holder and a bath plug.
Ms Smith said: "One of the reasons why people know a lot of the details about me is that people have chosen to focus on the details of my expenses. All of the receipts that I have put in are out there.
"When you put in a claim and you put in a receipt on which there are a number of items, obviously people can pick out one of them and say 'why did you claim for that?' but that is because you put in the whole of the receipt."
According to the leaked receipts, Ms Smith filed claims of £550 for a stone sink and console for the kitchen, £568.95 for two washing machines and £119.99 for a Vax carpet cleaner.
Some £405.37 went on plumbing, nearly £500 on a shower mixer, and 88p on a bath plug.
Ms Smith also reportedly bought a £1,000 fireplace, a 32-inch flat screen TV costing £369.99 and a £575 armchair.
Another £511.20 was spent on a sofabed, £72 on four scatter cushions, and £110 on bed linen.
Asked about the claims for pornographic films watched by her husband, she replied: "I feel personally sorry, cross and angry with myself that I made a claim that I shouldn't have made. I paid it back. I did the wrong thing."
It has also emerged that Transport Secretary Geoff Hoon and Chancellor Alistair Darling claimed for second homes and rented out their London apartments while living in taxpayer-funded flats.
Both say their claims were within the rules and openly declared.
The second homes allowance is meant to cover the costs of MPs staying away from home on parliamentary business and can be used towards mortgage interest and rent payments, hotel bills, as well as furniture, utility bills and upkeep costs - among other things.
MPs must designate a property as their main home - usually their base in London - then claim expenses on their "second" home, which is usually the constituency property.
The Committee on Standards in Public Life has brought forward its inquiry into the allowances system and is due to publish its recommendations for reform before the end of the year.
Meanwhile, the Parliamentary Commissioner for Standards, John Lyon, has confirmed he is investigating Harry Cohen, Labour MP for Leyton and Wanstead, who claims costs for his east London home because he lists a house 70 miles away in Colchester, Essex, as his main residence.
Mr Lyon is also looking into a complaint about Labour minister Tony McNulty, who claimed thousands of pounds in allowances for the house his parents lived in, in his Harrow East constituency.
Conservative leader David Cameron said he would not claim the second home allowance if he moved into Number 10 after the next election and would expect other ministers with grace-and-favour properties to do the same.
He has called for immediate reform to the MPs' expenses system, which he said was dragging politics "through the mud".
Lib Dem leader Nick Clegg, who will publish his own reform proposals this week, said: "It is clearly barmy for ministers to indulge in a form of double counting that enables them to enjoy two homes at the taxpayer's expense."