Eating Small Fish May Extend Lifespan, Research Indicates

Large fish like salmon and tuna often receive attention for their health advantages. However, new research published in Public Health Nutrition highlights the significant benefits of consuming smaller fish lower on the food chain. The study found a strong link between eating small fish, including bones and heads, and a reduced risk of mortality in women.

Nutrient-Rich Small Fish

Small edible saltwater fish are crucial sources of micronutrients when consumed whole with bones and organs. These nutrients play essential roles in preventing non-communicable diseases such as cardiovascular disease (CVD) and cancer. Some of the health benefits include:

• Antihypertensive effects;
• Atherosclerosis inhibition;
• Antitumor properties.

Small fish’s bones, eyes, and inner organs are rich in calcium and vitamin A. Unlike larger fish, whose bones and organs are usually discarded, small edible saltwater fish provide a unique benefit by being entirely consumable.

Small edible saltwater fish are less likely to carry contaminants like mercury and polychlorinated biphenyls (PCBs) than larger species such as tuna and swordfish.

Cultural Eating Habits in Japan

In Japan, people regularly consume various small edible saltwater fish types, including whitebait, Atlantic capelin (shishamo), Japanese smelt (wakasagi), small horse mackerel, young sweetfish, and small dried sardines. These fish are enjoyed in numerous ways:

• Raw or marinated in vinegar;
• Simmered in soy sauce;
• Salted and semi-dried;
• Deep-fried.

Fish like capelin and smelt typically range from 10-15 cm in length, while smaller fish such as whitebait are under 3.5 cm. These small edible saltwater fish are available as frozen or refrigerated products throughout the year. This habit extends beyond Japan to other Asian, African, and European countries. Consuming affordable small fish in developing regions can help alleviate severe micronutrient deficiencies.

Small Fish in the Mediterranean Diet

The traditional Mediterranean diet, celebrated for its heart-health benefits, features small edible saltwater fish like sardines and anchovies. While fresh varieties are ideal, canned options are both affordable and accessible. However, most canned anchovies are salt-cured and high in sodium, which can elevate blood pressure.

Small edible saltwater fish are a heart-healthy cornerstone of the Mediterranean diet. Their impressive culinary flexibility makes them ideal for various cooking methods and dishes. In Crete and other Greek islands, restaurants and tavernas offer a wide array of fish options. The most affordable choices include sardines (sardeles), anchovies (gavros), mackerel (kolios), bogue (gopa), and smelt (marides), prepared in numerous ways such as deep-fried smelt, fried sardines, grilled sardines, marinated sardines, and marinated anchovies.

Notably, there is a difference between anchovies and sardines: sardines are usually bigger and rounder, with a smaller mouth. Sardines are often preserved in olive oil, giving them a softer, milder taste, while anchovies are typically salt-cured, providing a stronger, more intense flavour.

Sardines packed in water or olive oil can be:

• Served on crackers or crusty, toasted bread with a dash of lemon
• Mixed like a tuna salad for sandwich fillings
• Incorporated into a Greek salad
• Tossed with pasta, combined either with tomato sauce or a blend of lemon, capers, and red pepper flakes

Small Fish Impact on Mortality Risks

Multiple cohort studies and meta-analyses have suggested a link between fish intake and reduced risks of all-cause, cancer, and CVD mortality, although findings for cancer mortality have been inconsistent. The specific effects of consuming small fish have not been thoroughly examined. The unique benefits of eating small fish whole, including their bones and organs, warrant focused research on the association between small fish intake and mortality risk rather than fish consumption in general.

Consuming small edible saltwater fish directly is more eco-friendly, bypassing the need to convert them into fish meal for farmed salmon, pork, and poultry. These animals also require grains, which demand land, water, pesticides, and energy, similar to the needs of grain-fed cattle.