All about fruitarianism with a long-term fruitarian, Lena

Several commercial fruits and vegetables contain small amounts of natural toxins. These natural toxins help protect the plants and create resistance to diseases and certain types of insects. See Secondary Metabolites in Leaves and Stems

The kernels within the pits of some stone fruits contain a natural toxin cyanogenic glycoside. These fruits include apricots, cherries, peaches, pears, plums and prunes. The flesh of the fruits itself is not toxic. Normally, the presence of cyanogenic glycoside alone is not dangerous. When kernels are chewed cyanogenic glycoside can transform into hydrogen cyanide, poisonous to humans. The lethal dose of cyanide ranges from 0.5 to 3.0 mg per kilogram of body weight. It is not recommended to eat the kernels inside the pits of stone fruits.

Ackee, akee or achee - Blinghia sapida - is a food staple in many Western Africa, Jamaican and Carribean diets. There are two main varieties, hard and soft ackees, that are available for consumption. Both canned and fresh forms of this fruit are consumed. However, unripe fruit contains natural toxins called hypoglycin that can cause serious health effects. The only part of this fruit that is edible, is the properly harvested and prepared ripe golden flesh around the shiny black seeds. The fruit is poisonous unless ripe and after being opened naturally on the tree.

Leonardo da Vinci

I have from an early age abjured the use of meat, and the time will come when men such as I will look upon the murder of animals as they now look upon the murder of men.

Food Energy

Food energy is chemical energy that animals derive from their food and molecular oxygen through the process of cellular respiration. Humans and other animals need a minimum intake of food energy to sustain their metabolism and to drive their muscles.

Organisms derive food energy from carbohydrates, fats and proteins as well as from organic acids, polyols, and ethanol present in the diet. Some diet components that provide little or no food energy, such as water, minerals, vitamins, cholesterol, and fiber, may still be necessary to health and survival for other reasons. 

Using the International System of Units, researchers measure energy in joules (J) or in its multiples; the kilojoule (kJ) is most often used for food-related quantities. An older metric system unit of energy, still widely used in food-related contexts, is the "food calorie" or kilocalorie (kcal or Cal), equal to 4.184 kilojoules. 

<>Fats and ethanol have the greatest amount of food energy per mass, 37 and 29 kJ/g (8.8 and 6.9 kcal/g), respectively. Proteins and most carbohydrates have about 17 kJ/g (4.1 kcal/g). 

Conventional food energy is based on heats of combustion in a bomb calorimeter and corrections that take into consideration the efficiency of digestion and absorption and the production of urine. 

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