A restaurant has been selling pizza saltier than sea water, according to new research by health organisations.
The research shows that takeaway pizza contains up to two and a half times more salt than the average supermarket pizza.
A pepperoni pizza from the Adam & Eve restaurant in Mill Hill, London contained 10.57 grams of salt.
The 2.73 grams of salt per 100 grams means the food is saltier than Atlantic seawater, which is 2.5 grams of salt per 100 grams.
The restaurant said it has already changed its recipe to make its pizza less salty as a result of the survey.
The survey analysed 199 margherita and pepperoni pizzas, from takeaways, pizza chains and supermarkets across the country.
Half of all takeaway pizzas surveyed contained the entire maximum daily recommendation of salt which is six grams.
Manufactured trans fat, which presents a serious health risk and can cause heart attacks and strokes, was found in 84% of the takeaway pizzas.
The target for salt content in pizza set by the Department of Health to be achieved by the end of 2012 is a maximum of 1.25 grams of salt per 100 grams. Only 16% of the takeaway pizzas tested met this target compared to three quarters of the supermarket pizzas.
A Pizza Express margherita pizza from a supermarket contained almost half the amount of salt than the restaurant equivalent.
However, despite containing a third less salt on average compared to takeaway pizzas, many supermarket pizzas were still classified as unhealthy. None of the surveyed supermarket pizzas were found to be low in salt, fat or saturated fat.
The survey by Consensus Action on Salt and Health (Cash) and the Association of London Environmental Health Managers (ALEHM) has been released as part of Salt Awareness Week.
This is organised each year by Cash to help raise awareness about the damaging effect of too much salt.
Professor Graham MacGregor, chairman of Cash, said: "Atlantic seawater contains 2.5 grams of salt per 100 grams.
This allows a comparison to be made between the amount of salt in food and seawater. It also allows consumers to realise the huge and unnecessary amount of salt added to food by the food industry."
He added: "The Government is not taking enough action to reduce the amount of salt in the takeaway sector. Salt puts up our blood pressure - the highest risk factor for stroke. Reducing our intake would save thousands of people suffering and dying from a stroke."
Responding to the survey, Gareth Leakey, the group manager of the Adam & Eve restaurant said:
"We thank Cash for their advice on the salt content of some of our pizzas, as we were unaware of the salt levels of combinations of certain traditional ingredients.
"As a small independent outlet it's very helpful and rare to have direction on such aspects of nutrition. We were informed of the survey two days ago and we have already changed our recipes and suppliers to lower the amount of salt in our pizzas to within recommended levels."
A Department of Health spokesman said: "Salt reduction is one of our key priorities as part of the Public Health Responsibility Deal. Many Responsibility Deal partners have made, and are continuing to make, considerable reductions in the levels of salt in their products and a large number of businesses have signed up to the salt reduction pledge - including companies that make pizzas. This is an important step that will help reduce salt intake and lower the risk of high blood pressure and resulting strokes or heart disease.
"We are working closely with the catering sector to encourage more businesses to sign up to the Responsibility Deal salt pledge so that we see salt reduction across the retail, food manufacturing and catering sectors.
"We look forward to seeing further reductions as more companies meet the targets."
If you're worried about the secret fat or salt content lurking in your food, take a look at HuffPost Lifestyle's round-up of foods that contain hidden fat traps.