Why Fall Is Prime Season for Blue Crabs and Jumbo Shrimp: A Nutritional Powerhouse With Caveats

[medi K / HEALTH IN NEWS] Autumn in Korea brings the ocean’s bounty to its peak, with blue crabs and jumbo shrimp—locally known as *kkotge* and *daeha*—taking center stage as nutrient-dense seasonal delicacies. Packed with protein, calcium, taurine, and other essential compounds, these shellfish are celebrated as health foods. Yet their benefits depend on individual constitution, underlying conditions, and proper preparation to maximize absorption and minimize risks.



Blue Crabs: Bone Health, Fatigue Recovery, and Beyond

Blue crabs deliver 118 mg of calcium per 100 grams—more than milk—and are particularly valuable for growing children, postmenopausal women at risk of osteoporosis, and older adults seeking to maintain bone density. The shells are rich in astaxanthin, an antioxidant with potency estimated at more than 500 times that of vitamin E, supporting immune function and delaying cellular aging. Selenium in the meat further protects cells and may reduce cancer risk.

For liver health, blue crabs contain roughly twice the taurine found in king crab, aiding detoxification and alcohol metabolism. Amino acids such as methionine and cysteine accelerate recovery from hepatic fatigue caused by heavy drinking or chronic stress.
At just 83 kcal per 100 grams, blue crabs are a high-protein (13.7 g), low-fat option. Chitosan helps lower cholesterol and inhibits thrombus formation, contributing to cardiovascular protection. Astaxanthin and taurine also safeguard retinal cells and scavenge free radicals, supporting vision.



Jumbo Shrimp: A Dieter’s High-Protein Ally

Jumbo shrimp provide 18.1 g of protein per 100 grams, including essential amino acids—leucine, lysine, and arginine—that promote muscle synthesis, immune resilience, and fatigue recovery. Taurine detoxifies the liver and mitigates alcohol-induced damage, while arginine alleviates exhaustion from overwork.

The synergistic action of taurine and chitosan improves circulation, moderates sympathetic overactivity, and helps stabilize blood pressure while protecting cardiovascular health. Brain benefits come from abundant DHA and omega-3 fatty acids, which maintain neuronal integrity and enhance memory and cognition. Astaxanthin neutralizes reactive oxygen species, slowing aging and preserving skin elasticity.

Who Benefits—and Who Should Proceed With Caution?

From school-age children and adolescents needing protein, calcium, and iron to postmenopausal women and seniors guarding against bone loss, blue crabs and jumbo shrimp are versatile. They also supply iron, folate, and vitamin B12 for women with anemia or during pregnancy—provided the shellfish are thoroughly cooked. Dieters appreciate the lean profile, and workers battling liver strain or accumulated fatigue find relief.

Caveats apply. Blue crabs contain about 300 mg of sodium per 100 grams; patients with hypertension or cardiovascular disease should limit intake, especially broth-based dishes where sodium leaches into the liquid. Their cooling nature in traditional East Asian medicine can trigger abdominal pain or diarrhea in those with cold constitutions or weak digestion.

Both species are high in purines, which metabolize to uric acid and can precipitate gout attacks; patients with hyperuricemia or gout should restrict consumption. Shellfish allergy may provoke urticaria, pruritus, or dyspnea. Though jumbo shrimp contain cholesterol, the HDL fraction helps reduce LDL; still, those with hyperlipidemia should moderate portions. Excessive intake risks histamine poisoning, manifesting as dizziness, headache, or itching—stop eating immediately if symptoms appear.



Safer, Smarter Preparation

Cook blue crabs and jumbo shrimp to an internal temperature of at least 185°F (85°C) to eliminate *Vibrio* vulnificus and other pathogens. Steaming, grilling, or soups ensure complete cooking.

Jumbo shrimp retain taurine, chitosan, protein, and DHA in shells and heads; eating them whole or frying the heads boosts nutrient uptake. Pair with vitamin C– and fiber-rich vegetables like cabbage or bell peppers to protect gastric mucosa, curb cholesterol absorption, and promote sodium excretion.

Avoid caffeine, which impairs calcium uptake from shrimp. Combining blue crabs with persimmons is generally safe, but spoiled ingredients heighten food-poisoning risk—use only fresh produce.

Select blue crabs with firm, elastic legs, a taut abdomen, and no off odors. Fresh jumbo shrimp appear translucent and glossy, with intact shells, heads, and legs. After cleaning, cook promptly; refrigerate up to two days or freeze for no longer than one month.

Oh Ha Eun / press@themedik.kr

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