Fat consumption and its association with age-related macular degeneration.

OBJECTIVE: To evaluate associations between past dietary fat intake and the prevalence of age-related macular degeneration (AMD). METHODS: Six thousand seven hundred thirty-four participants aged 58 to 69 years in 1990-1994 took part in this cohort study. Participants' nutrient intakes were estimated from a food frequency questionnaire at baseline. At follow-up from 2003 to 2006, digital macula photographs of both eyes were evaluated for early and late AMD signs. Logistic regression was used to estimate odds ratios, with adjustment for age, smoking, and other potential confounders. RESULTS: Higher trans-unsaturated fat intake was associated with an increased prevalence of late AMD; the odds ratio comparing the highest with the lowest quartile of trans fat was 1.76 (95% confidence interval, 0.92-3.37; P = .02). Higher omega-3 fatty acid intake (highest quartile vs lowest quartile) was inversely associated with early AMD (odds ratio, 0.85; 95% confidence interval, 0.71-1.02; P = .03). Olive oil intake (> or =100 mL/week vs <1 mL/week) was associated with decreased prevalence of late AMD (odds ratio, 0.48; 95% confidence interval, 0.22-1.04; P = .03). No significant associations with AMD were observed for intakes of fish, total fat, butter, or margarine. CONCLUSION: A diet low in trans-unsaturated fat and rich in omega-3 fatty acids and olive oil may reduce the risk of AMD.

Dietary omega-3 fatty acid and fish intake in the primary prevention of age-related macular degeneration: a systematic review and meta-analysis.

OBJECTIVE: To systematically review the evidence on dietary omega-3 fatty acid and fish intake in the primary prevention of age-related macular degeneration (AMD). METHODS: Seven databases were systematically searched with no limits on publication year or language using standardized criteria. Randomized controlled trials and prospective cohort, case-control, and cross-sectional studies were included. Of 2754 abstracts identified, 3 prospective cohort, 3 case-control, and 3 cross-sectional studies met the criteria. Measures of associations were pooled quantitatively using meta-analytic methods. RESULTS: Nine studies provided data on a total sample of 88 974 people, including 3203 AMD cases. A high dietary intake of omega-3 fatty acids was associated with a 38% reduction in the risk of late AMD (pooled odds ratio [OR], 0.62; 95% confidence interval [CI], 0.48-0.82). Fish intake at least twice a week was associated with a reduced risk of both early AMD (pooled OR, 0.76; 95% CI, 0.64-0.90) and late AMD (pooled OR, 0.67; 95% CI, 0.53-0.85). CONCLUSIONS: Although this meta-analysis suggests that consumption of fish and foods rich in omega-3 fatty acids may be associated with a lower risk of AMD, there is insufficient evidence from the current literature, with few prospective studies and no randomized clinical trials, to support their routine consumption for AMD prevention.

Dietary antioxidants and primary prevention of age related macular degeneration: systematic review and meta-analysis.

OBJECTIVE: To evaluate the effectiveness of dietary antioxidants in the primary prevention of age related macular degeneration (AMD). DESIGN: Systematic review and meta-analysis. DATA SOURCES: Search of seven databases without limits on year or language of publication, and retrieval of references in pertinent reviews and articles. METHODS: Two reviewers independently searched the databases and selected the studies, using standardised criteria. Randomised clinical trials and prospective cohort studies were included. Of the 4192 abstracts initially identified, 12 studies (nine prospective cohort studies and three randomised clinical trials) met the selection criteria and were included. Data extraction and study quality evaluation were independently reviewed, using standardised criteria. Results were pooled quantitatively using meta-analytic methods. RESULTS: The nine prospective cohort studies included 149 203 people, with 1878 incident cases of early AMD. The antioxidants investigated differed across studies, and not all studies contributed to the meta-analysis of each antioxidant. Pooled results from prospective cohort studies indicated that vitamin A, vitamin C, vitamin E, zinc, lutein, zeaxanthin, alpha carotene, beta carotene, beta cryptoxanthin, and lycopene have little or no effect in the primary prevention of early AMD. The three randomised clinical trials did not show that antioxidant supplements prevented early AMD. CONCLUSIONS: There is insufficient evidence to support the role of dietary antioxidants, including the use of dietary antioxidant supplements, for the primary prevention of early AMD.

Facts on fats.

Cardiovascular disease and age-related macular degeneration (AMD) may share common risk factors in their causal pathways. Decades of research from the cardiovascular sciences on fats have led investigators to focus on specific types of fats rather than total fat as a whole. They have established that saturated and trans-unsaturated fats (trans fats) are damaging to cardiovascular health while polyunsaturated fats, particularly the marine omega 3 fatty acids appear protective. This has led to a number of studies investigating the associations of fat and AMD. Though the causal relationship between fats and AMD remain unproven, some studies suggest that an association may be present. To be able to understand and interpret the study results and their implications, an understanding of the fats in the diet is important. This review aims to give an overview of fatty acids, particularly the trans-unsaturated fatty acids, and the relevant food groups.