Love boosts health — until marriage and three kids

After that things tend to get a bit stressful, particularly for the bride-to-be.

But the honeymoon glow lasts longer than most people think.

Couples with up to two children and people in same-sex relationships are among the happiest and healthiest, according to the Alere Wellness Index made up of scores for exercise, psychological wellbeing, nutritional health, alcohol, smoking, medical conditions and body mass.

Couples with three or more children aged under 16 have increased stress, according to the index, which is based on 50,000 surveys a year conducted by Roy Morgan Research.

Men in a same-sex relationship are prone to drinking too much and putting on weight.

Separated and divorced people are the least healthy, with poor psychological scores and high rates of smoking.

Single people, particularly women aged 35 –49, do worst on a psychological level, according to the index.

But things improve for