How healthy are you?
I like to push myself physically - sometimes to a fault, in that I don't listen to my body enough - and I can really become quite tired.

Do you worry about your weight?
I'm fairly concentrated on it, but I'm not the kind of musician who's going to get on a magazine cover with my stomach showing. I'm big boned and I can gain weight easily, especially because I'm quite gluttonous. When I'm on the road I work really hard, so it's easy to maintain a slimmish figure.

How much do you drink?
As I've got older I've learnt to make sure that I'm not totally ruined all the time. Now I just drink a couple of glasses of wine a night.

Attitude to taking drugs?
They are detrimental and sometimes hard to avoid. I had a great experience with narcotics. They have expanded my mind, maybe not as much as they have ruined it, but I think it's a part of life and being young and in the music and art scene. There are a lot worse things that people can do.

Have you ever had therapy?
Yes, briefly, a couple of years ago. I felt far better leaving my appointment than I did arriving. I didn't stick with it when I was on the road because I wouldn't do it over the phone - it wasn't that important to me.

Is sex important to you?
I'm someone who puts a lot of importance on love and intimacy. I'm a very physical person, and it's always been a big part of my life to connect with people. I'm lucky enough to travel with my husband. I think that's helpful.

How do you feel about plastic surgery?
It is not for me. My mother and my aunt [the McGarrigle Sisters] are an inspiration; their natural beauty really suits them. However, a few women I know have had surgery and it really works for them.

How do you relax?
I meet a lot of people, so it's great to have some alone time. Cooking helps me to relax, and I love to dry sauna. If I have free time I'll go to the Russian baths in New York for two hours.

What exercise do you take?
I like to jog and do yoga. If I'm at home in New York I usually walk about five miles a day. I'll go to the grocery store, put the food in my rucksack, and just keep as active as possible.

How much sleep do you need?
I like to get seven or eight hours a night, which allows me to get four or five sometimes and not feel completely crippled.

Are you happy?
I'm very happy. Being able to sing and play music brings me a great deal of joy and helps me to cope with a lot of sadness from my past.

If I hadn't been a musician, I would definitely be messed up.

'I swear by ...'
Stretching is helpful because you don't have to do extensive amounts of it to feel better. If I'm tired and waiting in a line at an airport with the band, it really helps to bend over and get the circulation going.

· Martha Wainwright's new album - I Know You're Married But I've Got Feelings Too - is out now