Getting old, fears over job security and relationships issues also leave a dark cloud hanging over millions on a daily basis.
The study also found that extreme anxiety has left many of us unable to concentrate at work, brought on endless sleepless nights, and even caused further rifts with their partners.
The research, which was commissioned by leading health and wellbeing mutual Benenden Health, found the average person endures 14 hours each week weighed down with worry.
Around 45% of those studied admitted stress and worry had directly affected their health.
Paul Keenan of Benenden Health said:
"It is a sad reality that stress is dominating our lives and having a severe impact on our work life, our quality of sleep and our personal relationships.
"The crunch comes when it begins to have a detrimental impact on our health - and 45% admit stress is already doing this.
"32% of people have even gone to the doctors because of worry or stress."
Concerns over low energy levels, fearing the aging process or work concerns featured highly in the list of the most common worries.
While relationship concerns, like whether a partner is right for them or even still in love with them, burden the mind of many a typical person.
In fact, the average adult experiences six nights every month where their sleep is disturbed or the quality reduced as a result of worrying.
And one in four feel they have a major worry they aren't dealing with properly or are deliberately avoiding.
One fifth has a friend or relative who they feel is currently running away from a problem while a third of people in relationships have a big worry they've kept secret from their partner - and these were most likely to be about finance problems.
Worryingly, one on four people doesn't feel they have anyone who they're able to talk with about their problems.
And three in ten bury a lot of things in order to get on with day to day life.
More than one in ten people have bank statements, bills or letters they have yet to open and they put these out of sight because they are too scared to read them.
Paul Keenan added:
"It's a small positive that 32% of people are taking stress issues to their doctor and seeking professional assistance.
"Brits need to ensure that stress is not taking over their lives without redress.
"They can do this by realising that a problem exists and not waiting until it is too late and their health is being severely impacted.
"The average person experienced 125 days over the last year where they had some sort of worry on their minds.
"There's a huge range of resources available to help people tackle stress - especially online where help is available from organisations such as Mind and the Stress Management Society."
TOP 30 BIGGEST WORRIES
- Stomach/ being overweight
- Getting old
- Lack of savings/ financial future
- Overall fitness
- Overdrafts and loans
- Low energy levels
- Credit card debt
- Paying rent/mortgage
- Job security
- Diet
- Keeping the house clean
- Finding a new job
- Sex life
- Generally unhappy
- Wrinkles or ageing appearance
- Whether or not I am attractive
- Physique
- Meeting work targets or goals
- Does my partner still loves me
- Whether I'll find or / are am with the right partner
- Whether I'm in the right career
- Friend or family issues
- Parenting skills
- Unhealthy reliance or addiction
- Driving
- Pet's health
- Child's health
- Dress sense
- Worrying I'm ill but yet to be tested/ seek help
- Partner is cheating/may cheat
- Sleepless nights
- Lost confidence
- Arguments with partner
- Reduced appetite
- Poor performance at work
- Distance from partner
- Avoided a social event
- Increased alcohol consumption
- Got a bit paranoid
- Nausea
14.31 hours per week worrying
744 hours worrying a year
45, 243 hours of worry in a lifetime
1,885 days of worry in a lifetime
5.2 years of worry