The benefits of adding fish to a vegetarian diet By Professor Luigi Fontana
According to the American and Canadian Dietetic Associations’ appropriately planned and supplemented vegetarian diet with fish is rich in vegetables, whole grains, legumes, seeds, nuts and fruits are nutritionally adequate, suitable for individuals in all stages of the life cycle and may provide multiple health benefits. Consuming vegetarian diets rich in minimally processed plant foods has been associated with a reduced risk of developing a range of cardiovascular diseases, diabetes, hypertension, cancer, and dementia.
Data from randomized clinic trials have confirmed a protective effect of vegetarian diet with fish for the prevention of diabetes, hypercholesterolemia, high blood pressure, and overweight.
However, accumulating evidence indicates some vegetarians, especially people consuming vegan diets (100% plant-based), are at greater risk of developing haemorrhagic stroke, bone fractures, and a range of vitamin- and mineral-deficiencies that are particularly dangerous for growing children and pregnant and breastfeeding women.
Vitamin B12, for example, is an essential vitamin produced by specific strains of bacteria that animals ingest when grazing grass. During digestion, large amounts of vitamin B12 are formed and incorporated in the animal’s meat, milk, and eggs. Fish and shellfish also contain considerable amount of vitamin B12; for instance, 100 grams of clams contain up to 49 µg of vitamin B12. Indeed, adding fish to a fibre-rich vegetarian diet has been shown to further improve metabolic health and reduce the risk of nutrient deficiencies, including iron, zinc, vitamin B12 and omega-3 fatty acids.
Fish-eating Inuit and Japanese populations traditionally had lower rates of heart disease compared to meat-eaters living in the US, North Europe and Australia. Other observational studies support these findings and suggest regular fish consumption can protect the heart and the brain, especially in people at higher than average risk of coronary heart disease. Eating four or more servings per week of vegetarian diet with fish, rich in long-chain omega-3 polyunsaturated fatty acids, seems to lower the risk of having a heart attack by 22 per cent compared to people who consumed seafood less than once a month.
Fishes rich in long-chain omega-3 polyunsaturated fatty acids mainly inhabit colder water and include salmon, mackerel, sardines, anchovies, herring, and tuna. Several mechanisms are responsible for the cardiovascular protective effects of omega-3, including lower inflammation and blood triglycerides, reduced blood pressure, lower platelet aggregation, and improved vascular function.
Vegetarian diet with fish, as we have already discussed, is also one of the best sources of vitamin B12. It exceeds meat in its vitamin B12 bioavailability, and unlike red meat, its consumption is associated with a lower risk of cardiovascular disease, stroke and colon cancer.