Health guidelines such as recommended intakes of salt and recommended exercise are unknown to members of the public, a survey for Nuffield Health has found.
The survey of about 2,000 people found that 90% of those surveyed were unaware of the daily guideline limit to salt intake.
A third (33%) were unconcerned about the amount of salt and sugar consumed as part of their diet.
Half (50%) said they were "making no attempt" to control the amount of sugar in their diet.
Of those surveyed, 40% were unaware that eating less salt can reduce blood pressure levels and lower the chances of having heart disease or a heart attack.
The link between high blood pressure and a stroke was unknown to 50% of those surveyed and 48% had no idea what their cholesterol levels were.
Exercise was also lacking - 18% of those surveyed never exercised while 40% exercise less than once a month.
Just 16% meet the guideline of 30 minutes of moderate exercise five times a week.
Those surveyed also reported getting seven hours or less sleep a night while 10% got less than five hours a night.
Alcohol consumption was also over recommended limits per week for 15% of men and 11% of women surveyed.
Dr Auldric Ratajczak, deputy medical director at Nuffield Health said: "Health guidelines are there to help people make the right choices and it's concerning to see that people either aren't aware of them or are choosing to ignore them.
"It's often just relatively small changes that can put you back on track. We shouldn't underestimate the clinical impact small changes can have in terms of good health and disease prevention."
