Fish Consumption Advice for Alaskans
The prevalence of diabetes, which was once rare among Alaskan and Canadian Eskimos, has steadily increased.30-34 Data from the Alaska Native diabetes registry for 1998 indicate that 1,666 Alaska Native people had diabetes.34 The overall age-adjusted prevalence rate increased from 15.7 to 28.3 per 1,000 population from 1985 to 1998, an 80% increase. Within the Alaska Native population, Aleut people had an age-adjusted prevalence during 1998 of 49.1 per 1,000, versus 18.5 per 1,000 for Eskimos. Unfortunately, the prevalence rate of 18.5 per 1,000 persons among Eskimos represents a 110% increase since 1985. Among regions, the percent increase in diabetes between 1985 and 1998 ranges from a low of 50% in the Kotzebue and Barrow regions to a high of 194% in the Norton Sound region. Diabetes prevalence rates among Alaska Native populations are now similar to the overall rate in the United States of 30.1 per 1,000 persons, a rate which has increased by just 13% since 1985. 34
Alaska Native people previously had a lower risk for death from coronary heart disease than did Alaskans of other races. Over the past several decades, this discrepancy has disappeared.35 Heart disease currently accounts for 55% of all deaths among Alaska Native people.36 These higher rates of heart disease are due to the higher prevalence of risk factors for coronary heart disease among Alaska Native people in recent years. Tobacco smoking rates are very high in Alaska Native people, store-bought foods have replaced traditional foods in the diet to varying extents, and modern conveniences such as motorized vehicles have led many Alaska Native people to a more sedentary lifestyle.37 Thus, the changing patterns of disease in Alaska Native people likely reflect increases in smoking, decreases in physical activity, changes in dietary practices, and increased obesity. 38,39
Increasing rates of diabetes and overweight/obesity are problems not only for Alaska Native people, but for all Alaskans. The prevalence of diabetes in the adult Alaska population has increased from 4.1% in 1996– 1998 to 5.6% in 2003–2005.40 The percentage of all Alaska adults categorized as above normal weight (body mass index 25) has increased from 52.7% in 1991–1993 to 61.4% in 2003–2005. 41
Fish consumption has been shown to reduce the occurrence of death from all causes,42 and many researchers have recommended maintaining or increasing fish consumption both for the cardiovascular disease prevention benefits as well as the benefits of preventing other chronic diseases. 43
Federal and International Criteria for Acceptable Mercury Exposure Levels in Humans
DPH recently reviewed information about the human health effects of mercury exposure through fish consumption.44 Sections of this review, or revised portions, are reprinted below for the purpose of these new state guidelines.
The critical target organ for methylmercury toxicity is the central nervous system. Three acute, high-dose poisoning episodes that occurred in Japan and Iraq during the period from 1953 through 1972 elucidated the severe, toxic effects of methylmercury.45-47 These outbreaks occurred with extremely high exposures to mercury and resulted in death or severe, irreversible neurological damage. Investigators also noted milder toxic effects.
In contrast to these high-dose poisoning episodes, the exposure of Alaskans to methylmercury through fish consumption is extremely small. Health effects of very low-dose mercury exposure from fish consumption, if any, are likely to be unmeasureable and of much less importance than many other variables that may impact neurological outcomes in children, such as pre-term birth, abuse and neglect, lower parental educational attainment, prenatal maternal alcohol and other drug use, and other factors. This is true even among the most sensitive segment of the population to the neurotoxic effects of methylmercury, i.e., the developing fetus.