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ARS Home » Plains Area » Grand Forks, North Dakota » Grand Forks Human Nutrition Research Center » Dietary Prevention of Obesity-related Disease Research » Research » Publications at this Location » Publication #99148
Title: CADMIUM CONSUMPTION FROM SUNFLOWER KERNELS AND ITS AVAILABILITY TO HUMAN VOLUNTEERS

Author
item Reeves, Phillip
item Nielsen, Emily
item VANDERPOOL, RICHARD - 5450-20-00

Submitted to: Proceedings Sunflower Research Workshop
Publication Type: Proceedings
Publication Acceptance Date: 1/14/1999
Publication Date: N/A
Citation: N/A

Interpretive Summary: Cadmium is a trace element found in small amounts in most foods. Instead of being a nutrient, it is most often thought of as a toxin. If humans eat too much of it over a long period of time, they might develop problems with kidney function. Most soils contain a small amount of cadmium. Some plants grown in these soils tend to take up cadmium and deposit it in their seeds. The sunflower is one of the plants that will do this. As a result, the seeds contain more cadmium than is found in most other grains. If humans eat a lot of the sunflower seeds over a long period of time, will they begin to show that they have too much cadmium in their bodies? We asked people to eat a prescribed amount of sunflower kernels as a part of their regular diet for almost one year. Then we measured the content of cadmium in their blood and urine as indicators of cadmium in the body. We also looked for small proteins that come out in the urine as a result of altered kidney function. We found that people who ate 9 ounces of kernels/week had no more cadmium in their urine or blood than those who ate no kernels. The amount of small proteins excreted in the urine were not different whether the person ate sunflower kernels or not. This study strongly suggests that people who eat a higher than the average amount of sunflower kernels per week are no more likely to have too much cadmium in their bodies than those who do not eat the kernels.

Technical Abstract: This study examined the effects of eating sunflower kernels (SFK) on the body retention of cadmium (Cd). Volunteers aged 23 to 59 yr, who reported low consumptions of SFK and other high-Cd food, participated. They were assigned to three groups and blocked by sex, age, and weight. One group was offered 255 g (9 oz) of roasted, unsalted, SFK (0.52 mg Cd/kg) per wk for 48 wk. Another group was offered 113 g (4 oz) of SFK and 142 g (5 oz) of unsalted peanuts per wk for 48 wk. A third group was offered 255 g of peanuts (0.11 mg Cd/kg) for the entire 48 wk of the study. The weekly intakes of Cd as a result of consuming the peanuts alone, the combination, or the SFK alone were 28, 75, and 133 ug, respectively. Volunteers were free-living and consumed their normal, self-selected diets in addition to the SFK and peanuts, throughout the study. Cd in red blood cells (RBC) was measured at the beginning of the study and at 12 week intervals until the end as an indicator of body Cd. Although the intake of Cd was increased almost 5-fold by consuming SFK, there was no significant change in RBC-Cd during the 48 wk for either men or women. However, RBC-Cd was significantly higher in women than men. Urine Cd was not significantly changed as a result of consuming SFK-Cd. Again, women excreted more urinary Cd than men. The urinary excretion of N-acetyl-beta-D- glucosaminidase (NAG), an indicator of kidney dysfunction, was unaffected by the consumption of Cd in SFK. Women excreted significantly (p<0.001) more NAG than men. Conclusion: consumption of 9 oz/wk of SFK containing 0.52 mg Cd/kg probably has no long-term adverse effect on RBC-Cd and the rate of Cd excretion in the urine; two measures of body accumulation of cadmium.