Energy & Metabolism

The brewed infusion of roasted, ground Coffea seeds, and the largest single source of polyphenols in many national diets simply…

Alertness and energy: Caffeine effects on alertness, reaction time and perceived fatigue are among the best-replicated findings in nutrition, demonstrated across many randomised trials. Two caveats: tolerance develops within days, and in habitual drinkers much of the morning lift is the wearing off of overnight withdrawal rather than performance above an unexposed baseline.

Leaves of the same plant as green tea, allowed to oxidise fully before drying, which converts most catechins into larger…

Alertness and energy: Black tea supplies caffeine, and caffeine has well-replicated short-term effects on alertness and reaction time. Doses per cup are lower and more variable than coffee, and much of the benefit in habitual drinkers is the wearing off of overnight withdrawal rather than a gain above baseline.

The metabolic and storage organ of cattle, and consequently one of the most nutrient-concentrated foods in the human diet by a…

Energy metabolism: Contains compounds associated with energy metabolism, including riboflavin, B12 and copper. Whether eating liver changes how energetic someone feels has not been tested directly; correcting a deficiency is the only situation where a change would be expected.

Leaves of Camellia sinensis heated soon after picking to stop enzymatic browning, which leaves the catechins largely intact. The…

Alertness and energy: Trials combining caffeine and L-theanine report modest short-term changes in attention and alertness tasks. Most use isolated compounds in doses chosen by the researchers rather than brewed tea, and results for theanine on its own are weak.

A small muscle running along the inside of the spine that does almost no work, making it the leanest and most tender cut on the…

Energy metabolism: Contains compounds associated with energy metabolism, principally thiamin, which is required by the enzymes that release energy from carbohydrate. A noticeable effect would only be expected in someone whose thiamin intake was low.

A small, soft organ meat with a milder flavour and finer texture than beef liver, which is why it dominates pâtés and parfaits.…

Energy metabolism: Evidence is limited for chicken liver improving energy levels. It is often described as a natural multivitamin, but no human trials test whether eating it changes fatigue or energy in people who are not deficient in the nutrients it supplies.