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Dietary Chromium Intake

Freely Chosen Diets, Institutional Diets, and Individual Foods

RICHARD A. ANDERSON,* NOELLA A. BRYDEN,

AND MARILYN M. POLANSKY

Vitamin and Mineral Nutrition Laboratory, Beltsville Human Nutrition Research Center,

US Department of Agriculture, ARS, Beitsville, MD 20705

Received January 31, 1991; Accepted February 17, 1991

ABSTRACT

Chromium content of 22 daily diets, designed by nutritionists to be well-balanced, ranged from 8.4 to 23.7 i~g/1000 cal with a mean _+ SEM chromium content of 13.4 + 1.1 ~g/1000 cal. Most dairy prod- ucts are low in chromium and provide <0.6 i~g/serving. Meats, poul- try, and fish are also low in chromium, providing 2 I~g of chromium or less per serving. Chromium contents of grain products, fruits, and vegetables vary widely, with some foods providing >20 ~g/serving. In summary, chromium content of individual foods varies, and is dependent upon chromium introduced in the growing, transport, processing, and fortification of the food. Even well-balanced diets may contain suboptimal levels of dietary chromium.

Index Entries: Trace elements; dietary chromium intake; food chromium; maturity-onset diabetes.

INTRODUCTION

Dietary chromium intake in the United States and other developed countries is suboptimal based on the min imum US suggested safe and adequate daily intake of 50 I~g (range is 50-200 ~g). Anderson and Koz-

*Author to whom all correspondence and reprint requests should be addressed.

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118 Anderson, Bryden, and Polansky

lovsky (1) measured the daily intake of chromium for seven consecutive days of 22 adult female and 10 male subjects. Not one subject had a mean 7-d intake of 50 vg. Mean + SEM intake for females was 25 _+ 1 ~g, and that for males was 33 --- 3 p~g. Similar results have been reported for England (2) and Finland (3), with slightly higher values for Canadian subjects (4).

This article describes dietary chromium intake of institutional and freely chosen diets, as well as chromium content of selected foods. Values for selected foods are presented as representative values, and should not be used as specific values to calculate dietary intake owing to the large variation in individual chromium concentrations of types and batches of foods.

/ TERIALS AND METHODS

All individual food items were analyzed as eaten. Foods requiring cooking were prepared in the diet kitchen of the Human Nutrition Research Center, Beltsville, Maryland; remaining foods were analyzed as purchased. The chromium analyses methods for foods and diets have been reported (1,5,6). A composite human diet sample, Reference Mate- rial 8431 (National Institute of Standards and Technology, Gaithersburg, MD), was used as an analytical check on the accuracy of the results. Under our conditions, we obtained a chromium concentration of 97 + 9 ng/g, certified 102 _+ 6 ng/g. Duplicate plate samples were collected for all freely chosen and institutional diet samples. Samples were collect- ed in polyethylene containers, weighed, and homogenized in a blender equipped with low-chromium steel blades to minimize chromium con- tamination.

RESULTS AND DISCUSSION

Chromium content of 22 daily diets designed by nutritionists to be well-balanced ranged from 8.4 to 23.7 Ixg/1000 cal with a mean _+ SEM chromium content of 13.4 --_ 1.1 p~g/1000 cal. Eleven female and eight male adult subjects collected freely chosen diets using the duplicate-plate technique. Mean ( + SEM) chromium content/1000 ca| for males was 18.6 + 2.8 and 12.5 + 0.8 for females. Mean chromium concentration for all subjects was 15 + 1.4, which is nearly identical to that of our much larger previous study (1). Therefore, dietary chromium content of freely chosen diets is similar to that of well-balanced diets designed by nutritionists.

We just completed a human study involving controlled low-chromi- um diets. Diets were comprised of normal foods, but specific batches of foods were selected for their low chromium concentration. Mean chromi- um concentration of the low-chromium diet was 5 + 0.2 ~g/1000 cal.

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Dietary Chromium Intake

Table 1 C h r o m i u m C o n t e n t of Selected Foods

119

Cr, ng /g '~ ~g / se rv ing

Dairy P roduc t s Who le milk, 1 c up - 244 g Skim milk, 1 cup = 244 g Butter, 1 pa t - 5 g Margar ine , 1 pat = 5 g A m e r i c a n cheese , 1 oz - 28 g Eggs, 1 egg = 50 g

Meats , Poul t ry , a nd Fish Beef cubes , 3 oz = 85 g Ch icken breast , 3 oz = 85 g Tu rkey breast , 3 oz = 85 g Tu rkey h a m , 3 oz - 85 g H a m , 3 o z - 8 5 g H a d d o c k , baked , 3 oz = 85 g

Gra in p r o d u c t s Waffles, 1 waffle = 75 g Who le w h e a t bread , 1 slice = 25 g Who le w h e a t roll, 1 roll = 26 g Engl ish muff in , W W , 1 muf f in - 100 g Dinne r roll, 1 roll = 25 g Rye bread , 1 slice = 25 g Bagel, egg, 1 bagel - 55g Crackers , trix, 2 crackers - 14 g Spaghet t i , 1 cup - 140 g Rice, whi te , 1 cup - 165 g Rice, b r o w n , 1 cup - 165 g

Fruits and vege tab les Banana, pee led , 1 m e d = 126 g Grapes , 10 g rapes = 50 g Apple , pee led , 1 m e d = 135 g Apple , u n p e e l e d , 1 m e d = 150 g Orange , peeled , 1 reed = 131 g Juice, grape , 1 cup = 250 g Juice, o range , 1 cup = 248 g Peas, 1 cup = 160 g Tomato , 1 m e d - 135 g Let tuce, 1 w e d g e = 135 g Celery, 1 stalk - 40 g Green beans , 1 cup = 135 g Carrots , raw, 1 carrot = 72 g French fries, 10 strips = 50 g Pota toes , m a s h e d , 1 c up = 210 g Broccoli, 1 c up = 185 g Juice, t omato , 1 cup = 240 g

C o n d i m e n t s Dress ing , T h o u s a n d Is land, 1 tbsp = 16 g Dress ing , French , 1 tbsp = 15 g

<0 .50 <0 .12 <0 .50 <0 .12

12 _+ 2 0.06 3 _+ 1 0.02

20 _+ 1 0.56 4 _+ 1 0.20

24 _+ 2 2.0 6 + 1 0.50

20 + 1 1.7 122 + 19 10.4

42 _+ 4 3.6 7 _+ 1 0.60

89 _+ 6 6.7 39 + 1 0.98 23 _+ 1 0.60 36 _+ 1 3.6 25 + 3 0.62 37 _+ 6 0.92 46 _+ 7 2.5

9 + 2 0.12 2 + 1 0.28 7 - + 1 1.2 4 -+ 1 0.66

8 _+2 1.0 2 _+0 0.10 3 _+ 1 0.40 9 + 1 1.4 3 +_ 1 0.39

30 _+ 1 7.5 9 + 2 2.2 5 _+ 1 0.80 7 _+ 1 0.94

13 _+ 2 1.8 3 _+ 1 0.12

16 _+ 0 2.2 4 _+ 1 0.29

24 _+ 1 1.2 18 _+ 1 2.7

118 _+ 0 22.0 6 _ + 1 1.5

11 _+ 1 0.18 12 _ 0 0.18

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120 Anderson, Bryden, and Polansky

Table 1 (Continued)

Cr, ng/g ~ ~g/serving

Pepper, 1 packet = 0.25 g 145 _+ 15 Salt, 1 packet = 1 g 5 _+ 1 Mayonnaise, 1 tbsp = 15 g 2 _+ 1 Mustard, 1 tsp = 5 g 48 + 6 Ketchup, 1 tbsp = 17 g 58 _+ 0 Barbecue sauce, 1 tbsp = 16 g 108 _+ 8 Maple syrup, 1 tbsp = 21 g 25 _+ 3 Jelly, grape, 1 packet = 14 g 14 _+ 1 Vinegar, 1 tbsp = 15 g 25 _+ 4 Sugar, 1 packet = 6 g 3 _+ 1

Miscellaneous Fruit punch, 1 cup -- 200 g 3 +_ 1 Orange sherbet, 1 cup = 193 g 7 _+ 1 Apple pie, 1/7 = 136 g 11 _+ 1 Cookies, oatmeal raisin, 4 cookies = 52 g 18 _+ 3 Cookies, vanilla sand., 4 cookies = 40 g 16 _+ 4 Cookies, choc. chip, 4 cookies = 42 g 82 + 30 Peanut butter, 1 tbsp = 16 g 38 _+ 3 Soybeans, 1 tbsp = 9 g 22 _+ 6

0.04 0.0l 0.03 0.24 0.99 1.73 0.52 0.20 0.38 0.03

0.60 1.4 1.5 0.94 0.64 3.4 0.6l 0.20

"Values are mean _+ SD of triplicate analyses.

Dietary chromium intake, as well as composition of diets, are impor- tant determinants in evaluating chromium nutritional status. Simple sugars increase chromium losses even when dietary intake is constant, leading to possible depletion of chromium stores (7).

Chromium content of selected foods is shown in Table 1. These values are a mean of triplicate analyses of separate samples from the selected foods described. Chromium content of individual lots of the same foods has been shown to vary widely (5,6). Mean chromium con- centration of beer samples ranged from 0.48 to 56 ng Cr/mL (5). Chromi- um content of the combined ingredients was not sufficient to account for the high levels of chromium in some beer samples. Therefore, a signi- ficant amount of chromium in beer, as well as other food items (6), originates from exogenous sources. However, this contaminating chro- mium does appear to be absorbed and utilized.

Dairy products appeared to be poor sources of dietary chromium (Table 1). Chromium content of meats was variable. Turkey ham, a processed luncheon meat, appeared to be a good source of chromium, but a significant amount of the chromium may have arisen from external sources, since beef, chicken, turkey, and ham are all lower in chromium.

Of the grain products, waffles, English muffins, and bagels seem to be the best sources of chromium. Again, it appears that chromium may be int roduced during the preparation, packaging, or handling.

Chromium content of fruits and vegetables was highly variable rang- ing from 0.1 to 22 i~g/serving. The origin of the chromium in the broccoli

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Dietary Chromium Intake 121

is being investigated to ascertain whether the chromium content is spuri- ous and variable. Peeling of apples decreased chromium content 70%, which may suggest external contamination. Chromium contents of peeled apples and oranges were similar, and bananas contained slightly greater amounts of chromium.

Of the condiments tested, barbecue sauce seemed to be an excellent source of chromium. Although black pepper is high in chromium, on a per serving basis, it contributes negligible amounts of chromium to the daily diets.

In summary, chromium content of individual foods varies substan- tially, and a significant portion of chromium present in foods likely originates from external sources during growing, processing, prepara- tion, fortification, and handling. Chromium content of diets is below the suggested intake, and most diets contain approx 15 t~g/1000 cal.

REFERENCES

1. R. A. Anderson and A. S. Kozlovsky, Am. J. Clin. Nutr. 41, 1177 (1985). 2. W. Bunker, M. S. Lawson, H. T. Delves, and B. E. Clayton, Am. J. Clin.

Nutr. 39, 797 (1984). 3. P. Koivistoinen, Acta Agric. Scand. Suppl. 22 (1980). 4. R. S. Gibson and C. A. Scythes, J. Biol. Trace Element Res. 6, 105 (1984). 5. R. A. Anderson and N. A. Bryden, J. Agric. Food Chem. 31, 308 (1983). 6. R. A. Anderson, N. A. Bryden, and M. M. Polansky, J. Food Comp. Anal.

Res. 1, 1303 (1988). 7. A. S. Kozlovsky, P. B. Moser, S. Reiser, and R. A. Anderson, Metabolism 35,

515 (1986).

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