In Traditional Korean Medicine (TKM), tuna is highly valued for its ability to replenish Qi (vital energy) and nourish the Blood due to its rich protein content. Consuming it as sashimi allows you to fully absorb unprocessed nutrients and healthy unsaturated fatty acids. However, tuna has a significantly 'cold' nature. For those with Spleen Deficiency (weak digestion) or a cold abdomen, relying solely on sashimi can lead to indigestion and the accumulation of 'Phlegm-fluid' (metabolic waste) in the body. For busy professionals, canned tuna offers unbeatable convenience, but the added oil and sodium are the primary issues. Excessive salt intake can cause edema and hinder circulation, creating an environment where 'Blood Stasis' (stagnant blood) easily forms. If you choose canned tuna, I suggest straining the oil thoroughly and briefly rinsing the meat in boiling water to reduce sodium. Ultimately, fresh sashimi is ideal for those with internal heat who need better circulation, while those with a cold constitution should eat canned tuna stir-fried with vegetables to consume it warm. Remember, the key to a successful diet starts with observing your own digestive health.