The study of 2,000 adults in relationships found nearly three quarters worry about the physical state of their other half.
One in three even admitted they regularly plead with their partner to change their lifestyle, to no avail.
Dr Petra Simic, Clinical Director at Bupa Health Clinics, which commissioned the study, said: “The research shows that people put more focus on their loved ones’ health at the cost of their own.
‘’It’s wonderful to see what a caring nation we are, but it’s important to understand that looking after ourselves actually gives us the ability to look after others, and is just as important.
‘’Regardless of the time of year, couples can work together on setting goals and helping each other to achieve them.
“In some cases, a professional opinion can help to motivate people to make healthier choices.
‘’Both parties taking their concerns to their GP or getting a health assessment will not only stop that persistent worrying, but you’ll both come away with key things to focus on.”
The results mean millions of Brits will be setting resolutions for their partners in 2018.
The most common pledges are getting them to eat healthier, lose weight and take up exercise.
One in four will encourage their other half to reduce their stress levels, with just under one sixth prompting their partner to strike a better work-life balance.
Nearly two in three adults even admitted putting the health of their significant other ahead of their own.
Reasons given include the belief they’re healthy and don’t need to worry about their own wellbeing, or admitting they’ll address their own health issues if and when any symptoms become problematic.
The poll of 1,000 men and 1,000 women also found nearly two thirds of adults admit to making tactical choices in an attempt to improve their partner’s health.
Swapping food for low-fat options, hiding treats and reducing sugar in hot drinks are among the sneaky tricks being employed to manage companion’s health.
The research, commissioned by Bupa Health Clinics, also revealed nearly one in seven will go to bed earlier to improve their partner’s sleeping habits.
Others have even made personal sacrifices to help their loved one such as quitting smoking themselves and going on a diet as a couple.
One even gave their significant other a hard dose of reality by measuring out sugar into a jug to show them how much they’d consumed that day.
Nearly 30 per cent will even go as far to book doctor’s appointments for their partner, with 22 per cent agreeing it’s because their loved one is too lazy to book their own.
And over one quarter said their significant other is simply “too busy to book their own”.
Top concerns about the health of our other halves:
1. Getting stressed easily
2. Not sleeping enough
3. Niggling ailments like back pain or a persistent cough
4. Doing no exercise
5. Working too hard
6. Being overweight
7. Eating too much junk food
8. Drinking alcohol regularly
9. Rarely walking anywhere
10. High blood pressure