Reese Witherspoon says her ''anxiety manifests as depression''.

The 44-year-old actress has children Ava, 20 and Deacon, 16, with her ex-husband Ryan Phillippe and Tennessee, seven, with husband Jim Toth and revealed that she had mental health struggles after welcoming two of her kids.

Speaking on Jameela Jamil's I Weigh podcast, Reese explained: ''I definitely had anxiety, my anxiety manifests as depression so I would get really depressed. My brain is like a hamster on a wheel and it won't come off, I've been managing it my entire life.

''I've had three kids. After each child I had a different experience... One kid I had kind of mild postpartum, and one kid I had severe postpartum where I had to take pretty heavy medication because I just wasn't thinking straight at all, and then I had one kid where I had no postpartum at all.''

She also revealed she had a particularly tough time after giving birth to Ava, because she didn't know what to expect.

Reese explained: ''We don't understand the kind of hormonal rollercoaster that you go on when you stop nursing. No one explained that to me.

''I was 23 years old when I had my first baby and nobody explained to me that when you wean a baby, your hormones go into the toilet. I felt more depressed than I'd ever felt in my whole life. It was scary.''

Reese's former husband Ryan, 45, previously spoke out about his own mental health struggles, explaining: ''You know, depression has been a huge obstacle for me ever since I was a child. As you get older I think it decreases some, but I'm just innately kind of a sad person.

''I'm empathetic, and I take on the feelings of others and transpose myself into the position of others. I see it in my daughter [Ava].

''She has it, and I wish to hell she didn't. It's just, some people do have this pervading sort of sadness, or they're so analytical that they can kind of take the fun out of things because they think too much.'

''It can ruin your f**king life. But I'd prefer to suffer through the sadness than to be a complete moron with no feelings.''