Carotenoids

They are yellow, orange, and red pigments in plants. The most common carotenoids in a Western diet are alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, zeaxanthin and lycopene. Each of these carotenoids carries a distinct set of actions, benefits and originating fruits and vegetables. There are more than 600 carotenoids.

Carrots, yams, sweet potatoes, papaya, watermelon, cantaloupe, mangos, spinach, kale, tomatoes, bell peppers, and oranges are among the fruits and vegetables in which carotenoids can be found.

In order to be properly absorbed, carotenoids should be consumed with a fat. Carotenoids are associated with antioxidant activity, eye health, immune system activity, intercellular communication, and reduced risk of cancer and cardiovascular disease, according to the Linus Pauling Institute.

The body can convert alpha-carotene, beta-carotene and beta-cryptoxanthin into vitamin A (retinol), which is associated with anti-aging and immune system function. Lutein and zeaxanthin are the only carotenoids found in the retina and are associated with lower risks of macular degeneration.

More Egg Facts

Eggs contain very little saturated fat (1.5 grams per large egg) and no trans fat. A medium egg contains about 63 calories and a large about 74 calories.

The nutrients in eggs can play a role in weight management, muscle strength, healthy pregnancy, brain function, eye health, and more.

Egg yolks are a great source of choline, an essential nutrient. Two eggs provide about 250 milligrams of choline. Choline also aids the brain function by maintaining the structure of brain cell membranes, and is a key component of the neuro-transmitter that helps relay messages from the brain through nerves to the muscles.

Lutein and zeaxanthin, two antioxidants found in egg yolks, help prevent macular degeneration, a leading cause of age-related blindness and may even reduce the risk of cardiovascular disease.

Eggs have the highest nutritional quality protein of all food sources. Protein is a source of energy, but its main role in the body is growth and repair. It helps in the formation of muscles, hair, nails, skin and organs, such as the heart, kidneys and liver.

Vitamins and minerals in eggs include:
Biotin - helps cell metabolism and the utilization of fats, proteins and carbohydrates
Calcium - for building and maintain bones and teeth
Cephalin - a phosphorus-containing lipid found in tissues
Folate - for growth
Iodine - to ensure proper function of the thyroid gland
Iron - to produce hemoglobin, which carries oxygen around our bodies maintenance of healthy cells
Lecithin - contains acetylcholine which has been proven to help brain function
Pantothenic acid (Vitamin B5 ) - releases energy from our food for our body to use
Phosphorous - helps build strong bones and teeth
Selenium - antioxidant that protects our body and immune system
Thiamine - to turn carbohydrates into energy our body can use
Vitamin A (retinal) - for growth and eye health
Vitamin B12 (riboflavin) - for brain and nervous system functions and blood formation
Vitamin D - important in bone health.
Vitamin E - antioxidant to protect our bodies against disease
Zinc - helps in growth, wound healing, blood formation and maintenance of tissues.

Eliminating eggs from your diet because you are concerned about cholesterol is of no value and you lose the dietary benefits. Harvard Medical School and Mayo clinic agree that even though yolks contain cholesterol, very little of it actually makes it into your bloodstream, where it matters.

Fresh vs. Frozen

In two recent studies from Britain, researchers purchased a half dozen different kinds of fruit and vegetables, all of which came in two varieties: fresh and frozen. After buying them and then having them chill out in either a fridge or freezer for three days, researchers conducted 40 tests to compare their nutritional content.

Turns out the frozen varieties were richer in health-boosting vitamins and antioxidants. In fact, frozen broccoli had four times more beta-carotene than its fresh counterpart, while frozen carrots had three times more lutein and double the beta-carotene as well as greater levels of vitamin C and polyphenols. Raspberries and peas performed about the same, whether they were fresh or frozen.

While it is true that foods gradually lose nutrients as they move through the supply chain, that chain is far longer for fresh produce. Fruits and vegetables are regularly held in storage for up to a month before you ever see them. Plus, according to study author Graham Bonwick Ph.D., a professor of applied biology at the University of Chester, once they hit your refrigerator  the nutritional loss escalates. It is probably due to the plant's continuing metabolic activity and how cells react to oxygen and exposure to artificial dark-light cycles.

A recent study from Rice University and the University of California at Davis found that the fluorescent lights of supermarkets and the constant darkness of your refrigerator affects fruit and vegetable circadian clocks so that they excrete fewer glucosinolates, compounds with cancer-fighting properties.

"Produce's degradation reactions are very much slowed by lowering the temperature to freezing levels," Bonwick says. "Furthermore, when you freeze produce, the water present in the cells of the food is locked up as ice, slowing or preventing these processes that require the presence of free water." Since produce in the freezer section was frozen solid almost immediately after being picked, it is preserved at its nutritional peak.

The truth About Egg Yolk Color

Americans eggs tend to have bright yellow yolks, because of what they feed feed the hens. Egg yolk color is almost entirely influenced by its diet. If you feed yellow corn it shows and if you feed birds white corn, the egg yolks are more white. In South America, hens that peck at red annatto seeds lay eggs with yolks ranging from pink to orange to deep reddish.

The yellow color in egg yolks, as well yellowish chicken skin and fat, comes from pigments found in plants.

In most parts of the world, diners prefer their yolks with a bit more color so commercial feeds often contain lutein as an additive, although yellow maize, soybeans, carrots, and alfafa powder will also add the color.

Many egg eaters assume that darker yolks are a sign of higher nutritional value. That is not true. Although chicken feed does influence the nutritional value of birds and their eggs, researchers say yolk color does not tell you anything about nutritional value. When it comes to taste, slap a few eggs next to a huge hunk of bacon and the taste becomes awesome, regardless of yolk color.