were asked to participate in a survey describing the menus and serving system in the canteen .
worksite information was obtained on number of meals served , occupation ( physically exacting to sedentary work ) , sex distribution , and canteen serving system to make sure that the final distribution would match the country as a whole .
two worksites refused to participate because of lack of time and one worksite was excluded to match the desired average distribution .
afterwards , the 20 worksites were asked to participate in the present study focusing on individual canteen food intake .
five of the 20 worksites refused to participate with the following reasons : lack of time ( three worksites ) or concerns of the employees ' reaction to the study ( two worksites ) .
eight of the worksites that agreed to participate mainly served buffet style and seven of the worksites served  la carte line .
the double portion technique with subsequent chemical analysis was used to quantify actual lunch intakes at the worksite canteens .
duplicate portions were collected from a total of 12 customers at each canteen on two different days ( six samples per day ) .
employees were asked at random to participate in the study , and in average two persons at each canteen rejected to participate .
all items of the meal including bread , spread , fruit , dessert , etc .
after the employees finished eating their lunch , they were asked to return the plates to the technicians in order to record / subtract plate waste .
the duplicate portions were individually mixed and homogenized in a grindomix type gm200 ( retch ) .
fast food was defined as food that can be eaten without the use of knife and fork . before the data collection
was carried out , a survey was performed to study the consumption of various kinds of fast food in denmark , and the result of this survey was used to plan the data collection to be representative for the consumption of fast food in denmark .
fast food samples were collected from 52 retail places representing both city ( aarhus ) and provincial towns , including pizzerias , major burger chain restaurants , outlets selling fast food , hot - dog stands , kiosks , and petrol stations .
a total of 250 samples were collected in the period february 2004 to june 2005 .
the samples were subdivided into seven groups of fast food and further divided into 45 different subgroups .
the seven main groups were : burgers , sandwiches , pitas , durum rolls , sausages , grilled meals , and pizzas .
three items of each of the 250 fast foods were collected , weighed separately , then mixed and homogenized in a grindomixer ( retsch ) and kept in plastic bags at 18c until analysis .
moreover , one sample of each fast food was separated and all components were weighted .
the chloride ion concentration was determined by potentiometric titration with silver nitrate solution , and salt content was estimated from the chloride content .
analyses of the content of protein , fat , and ash were performed according to procedures given by the nordic committee on food analysis ( 1012 ) .
dry matter content was determined by drying in a vacuum oven at 70c to constant weight .
carbohydrate and energy content were calculated from contents of dry matter , protein , fat , and ash ( 13 ) .
canteen meals were categorized into four groups : ( 1 ) hot meals , ( 2 ) sandwiches ( mainly open sandwiches ) , ( 3 ) salad , or ( 4 ) a combination of hot meals / sandwiches and salad / fruit / snack vegetables . as
some fast food is eaten as combo menus with a combination of e.g. sausages and bread , ketchup , mustard , burger in combination with chips , etc . , the salt content of typical menus was calculated .
the calculations were made by using food composition table values ( 14 ) for the salt content and the analyzed value for the main part of the meal .
it was not possible to give standard deviations for the salt contents in meals as these are calculated values .
comparisons of salt content in meals between men and women , and between different kinds of meals were done using students t - test .
data processing was done with spss version 14.0 ( chicago , il , usa ) .
the recruitment took place in two steps . a total of 23 worksites with in - house catering facilities representing both city ( aarhus ) and smaller towns all situated in jutland ,
were asked to participate in a survey describing the menus and serving system in the canteen .
worksite information was obtained on number of meals served , occupation ( physically exacting to sedentary work ) , sex distribution , and canteen serving system to make sure that the final distribution would match the country as a whole .
two worksites refused to participate because of lack of time and one worksite was excluded to match the desired average distribution .
afterwards , the 20 worksites were asked to participate in the present study focusing on individual canteen food intake .
five of the 20 worksites refused to participate with the following reasons : lack of time ( three worksites ) or concerns of the employees ' reaction to the study ( two worksites ) .
eight of the worksites that agreed to participate mainly served buffet style and seven of the worksites served  la carte line .
the double portion technique with subsequent chemical analysis was used to quantify actual lunch intakes at the worksite canteens .
duplicate portions were collected from a total of 12 customers at each canteen on two different days ( six samples per day ) .
employees were asked at random to participate in the study , and in average two persons at each canteen rejected to participate .
all items of the meal including bread , spread , fruit , dessert , etc .
after the employees finished eating their lunch , they were asked to return the plates to the technicians in order to record / subtract plate waste .
the duplicate portions were individually mixed and homogenized in a grindomix type gm200 ( retch ) .
fast food was defined as food that can be eaten without the use of knife and fork . before the data collection
was carried out , a survey was performed to study the consumption of various kinds of fast food in denmark , and the result of this survey was used to plan the data collection to be representative for the consumption of fast food in denmark .
fast food samples were collected from 52 retail places representing both city ( aarhus ) and provincial towns , including pizzerias , major burger chain restaurants , outlets selling fast food , hot - dog stands , kiosks , and petrol stations .
a total of 250 samples were collected in the period february 2004 to june 2005 .
the samples were subdivided into seven groups of fast food and further divided into 45 different subgroups .
the seven main groups were : burgers , sandwiches , pitas , durum rolls , sausages , grilled meals , and pizzas .
three items of each of the 250 fast foods were collected , weighed separately , then mixed and homogenized in a grindomixer ( retsch ) and kept in plastic bags at 18c until analysis .
moreover , one sample of each fast food was separated and all components were weighted .
chloride content was determined and salt content was estimated by multiplying with 1.648 . the chloride ion concentration was determined by potentiometric titration with silver nitrate solution , and salt content was estimated from the chloride content .
analyses of the content of protein , fat , and ash were performed according to procedures given by the nordic committee on food analysis ( 1012 ) .
dry matter content was determined by drying in a vacuum oven at 70c to constant weight .
carbohydrate and energy content were calculated from contents of dry matter , protein , fat , and ash ( 13 ) .
canteen meals were categorized into four groups : ( 1 ) hot meals , ( 2 ) sandwiches ( mainly open sandwiches ) , ( 3 ) salad , or ( 4 ) a combination of hot meals / sandwiches and salad / fruit / snack vegetables . as
some fast food is eaten as combo menus with a combination of e.g. sausages and bread , ketchup , mustard , burger in combination with chips , etc . , the salt content of typical menus was calculated .
the calculations were made by using food composition table values ( 14 ) for the salt content and the analyzed value for the main part of the meal .
it was not possible to give standard deviations for the salt contents in meals as these are calculated values .
comparisons of salt content in meals between men and women , and between different kinds of meals were done using students t - test .
data processing was done with spss version 14.0 ( chicago , il , usa ) .
the intake is higher in men compared with women when given as gram per meal , but there was no gender difference per energy unit .
salt intake in meals eaten in worksite canteens ( meansd ) difference between genders . of the 180 meals , 109 ( 61% ) had a salt content at or below 1.0 g per 100 g. eleven ( 6% ) of the meals had a salt content at or below 7 g per 10 mj .
five ( 3% ) of the meals had a salt content equal to or more than the recommended daily salt intake of 7 g. the salt content in various canteen meals is given in table 2 , per 100 g , per portion , and per 10 mj .
the salt content in salad was significantly lower than the salt content in other meal types when expressed in all three ways , but no significant differences were found between salt content in the other meal types with mean salt content ranging from 13.0 to 16.1 g per 10 mj .
salt intake from various meal options eaten in worksite canteens ( meansd ) p<0.05 compared with the other meal options .
table 4 shows the salt content in selected subgroups of fast food . in only 17 ( 7% ) of the fast foods
salt content in some commonly eaten complete fast food meals were estimated to range from 4.4 to 9.1 g per meal or 7.7 to 21 g per 10 mj ( table 5 ) .
salt content in various kinds of fast food ( meansd ) salt content in selected types of fast food ( meansd ) salt content in fast food meals
this study shows that the salt content in both worksite canteen meals and fast food is high compared to the recommended daily intake .
when expressed as g salt per 10 mj , the mean salt content in canteen meals was generally even higher than the salt content in fast food .
the present study shows that a single canteen meal may provide more than half of the daily recommended amount of salt and that some meals even contain more than the daily recommended amount .
although only few studies have assessed salt content in canteen meals , a high content of salt seems to be a general finding .
a study from france ( 15 ) found a mean content of 3.4 g salt in lunch meals from various catering establishments .
likewise , a recent belgian study found a salt content of 3.1 g in lunch meals consumed at ghent university ( 16 ) .
if the mean amount of salt in the lunch meal is extrapolated to a daily intake , it would be 14.6 g per day for a person consuming 10 mj .
this is a very high value compared to the recommended long - term goal of 56 g per day .
the extrapolation assumes that the salt content per mj is similar in all meals consumed during the day .
thus , if a hot meal is consumed both as lunch and dinner then the daily salt intake is expected to be even higher than the extrapolated mean intake of 14.6 g per day and the opposite must be true if mainly salad meals are consumed .
the salt content in breakfasts have not been investigated , but is expected to vary according to the kind of food eaten ; some breakfast cereals , e.g. corn flakes have a high salt content whereas others , e.g. oat have a very low content ( 13 ) .
a limit at 1.0 g salt per 100 g has been set for the use of keyhole labeling ( a label which emphasizes the better choice within a food group ) for ready - prepared dishes in denmark ( 17 ) .
more than half ( 61% ) of the worksite canteen meals was at or below this limit .
however , the limit seems rather high as one meal with a content of 1.0 g salt per 100 g can provide an amount close to the daily recommended intake . expressed per energy unit , the content of salt is very high in the worksite canteen meals . in order to reach the recommendation of salt intake , salt intake from all sources
must be reduced including meals consumed within and outside the homes . to our knowledge ,
no intervention studies with focus on salt intake has been carried out in worksite canteens .
a study that focused on fat and salt content in school cafeterias ( 18 ) found at follow up among the 88 participating schools that none reached the goal of less than 2.5 g salt in a lunch meal , although they have paid attention on several guidelines to lower salt intake ( 18 ) .
no data exist for the number of persons eating a meal daily in a worksite canteen in denmark .
fast food is eaten frequently in many countries and the frequency of fast food use has increased dramatically since the 1970s ( 7 ) . in denmark , the intake of fast food among 418-year old boys and girls has increased from 1995 to 2004 ( 19 , 20 ) , and the actual intake in the group 1518-year old is a little above 100 g a day .
the present study shows , not surprisingly , a high content of salt in fast food meals .
thus , a pizza meal , for instance , can provide up to twice the recommended daily intake . in the usa it has been found that the intake of salt was significantly higher among individuals who eat fast food regularly than among individuals who do n't eat fast food ( 20 ) . likewise , a study found that salt intake was significantly higher among young women who were classified as having a fast food eating pattern than among women classified with other eating patterns ( 8) . in contrast , no difference in salt intake was found between a day when fast food was eaten and a day fast food was not eaten in another usa study ( 21 ) .
fast food consumption has been related to higher energy intake , overweight , and poor diet quality ( 22 ) , and the risk of hospital admissions for acute coronary heart disease was higher in regions with greater numbers of fast food services than in regions with few ( 23 ) .
the reason why fast food is regarded as unhealthy is mainly the high content of fat , trans fatty acids and energy , and the high salt content is another reason why fast food in general is an unhealthy choice . in conclusion ,
if the recommendation for salt intake should be reached it is necessary to lower the salt content in these meals .
the authors have no conflicts of interest and did not receive any funding or benefits from industry to conduct this study .
 backgrounda high salt ( = nacl ) intake is associated with high blood pressure , and knowledge of salt content in food and meals is important , if the salt intake has to be decreased in the general population.objectiveto determine the salt content in worksite canteen meals and fast food.designfor the first part of this study , 180 canteen meals were collected from a total of 15 worksites with in - house catering facilities . duplicate portions of a lunch meal were collected from 12 randomly selected employees at each canteen on two non - consecutive days . for the second part of the study , 
 a total of 250 fast food samples were collected from 52 retail places representing both city ( aarhus ) and provincial towns . 
 the canteen meals and fast food samples were analyzed for chloride by potentiometric titration with silver nitrate solution , and the salt content was estimated.resultsthe salt content in lunch meals in worksite canteens were 3.81.8 g per meal and 14.75.1 g per 10 mj for men ( n=109 ) , and 2.81.2 g per meal and 14.46.2 g per 10 mj for women ( n=71 ) . 
 salt content in fast food ranged from 11.82.5 g per 10 mj ( burgers ) to 16.34.4 g per 10 mj ( sausages ) with a mean content of 13.83.8 g per 10 mj.conclusionsalt content in both fast food and in worksite canteen meals is high and should be decreased . 
Methods
Worksite canteen meals
Fast food
Analyses
Calculations
Statistics
Results
Discussion
Conflict of interest and funding