All about fruitarianism with a long-term fruitarian, Lena

Retinoids retinol, retinal, and retinoic acid - 3 active forms of vitamin A - "preformed" vitamin A.

Beta carotene can easily be converted to vitamin A by the human body. 

Large amounts of supplemental vitamin A (but not beta carotene) can be harmful to bones.

Vitamin A keeps tissues and skin healthy, plays an important role in bone growth. Diets rich in the carotenoids alpha carotene and lycopene seem to lower lung cancer risk. Carotenoids act as antioxidants. Foods rich in the carotenoids lutein and zeaxanthin may protect against cataracts. Essential for vision lycopene may lower prostate cancer risk.

Recommended daily amount: 700 mcg - 900 mcg or 3 mg - 6 mg beta-carotene (~ 1 cup of raw cantaloupe or sweet red peppers, or 2 mangoes, or 1/5 of one baked sweet potato). 

Because the body converts all dietary sources of vitamin A into retinol, 1 mcg of physiologically available retinol is equivalent to the following amounts from dietary sources: 1 mcg of retinol, 12 mcg of beta-carotene, and 24 mcg of alpha-carotene or beta-cryptoxanthin. From dietary supplements, the body converts 2 mcg of beta-carotene to 1 mcg of retinol.

Isaac Bashevis Singer

What do they know-all these scholars, all these philosophers, all the leaders of the world - about such as you? They have convinced themselves that man, the worst transgressor of all the species, is the crown of creation. All other creatures were created merely to provide him with food, pelts, to be tormented, exterminated. 

Dietary Reference Intake DRI

Dietary Reference Intakes (DRIs) are reference values that are quantitative estimates of nutrient intakes to be used for planning and assessing diets for healthy people. They include both recommended intakes and upper intake levels.

Although the reference values are based on data, the data are often insufficient or drawn from studies that had limitations in addressing the question. Scientific judgment is required in setting the reference values. 

  • EAR - Estimated Average Requirement - a nutrient intake value that is estimated to meet the requirement of half the healthy individuals in a group.
  • RDA - Recommended Dietary Allowance - the average daily dietary intake level that is sufficient to meet the nutrient requirement of nearly all (97 to 98 percent) healthy individuals in a group.
  • AI - Adequate Intake: a value based on observed or experimentally determined approximations of nutrient intake by a group of healthy people.
    Used when an RDA cannot be determined.
  • UL - Tolerable Upper Intake Level - the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects to almost all individuals in the general population. As intake increases above the UL, the risk of adverse effects increases. Apple