Vitamin A: What's it Good For?

This is part of our regular series of articles on individual vitamins and minerals and what their purpose is in the body. See our article archives where you can do a search for a specific nutrient we have covered. You must be a Circkles Club Member to use our archives however. Membership is FREE.

Vitamin A is the name of a group of fat-soluble retinoids, including retinol, retinal, retinoic acid, and retinyl esters. Vitamin A is involved in immune function, vision, reproduction, and cellular communication and is critical for vision as an essential component of rhodopsin, a protein that absorbs light in the retinal receptors, and because it supports the normal differentiation and functioning of the conjunctival membranes and cornea. Vitamin A also supports cell growth and differentiation, playing a critical role in the normal formation and maintenance of the heart, lungs, kidneys, and other organs.
Two forms of vitamin A are available in the human diet: preformed vitamin A (retinol and its esterified form, retinyl ester) and provitamin A carotenoids. Preformed vitamin A is found in foods from animal sources, including dairy products, fish, and meat, especially liver.

Table 1: Recommended Dietary Allowances (RDAs) for Vitamin A [5]
Age Male Female Pregnancy Lactation
0–6 months* 400 mcg RAE 400 mcg RAE    
7–12 months* 500 mcg RAE 500 mcg RAE    
1–3 years 300 mcg RAE 300 mcg RAE    
4–8 years 400 mcg RAE 400 mcg RAE    
9–13 years 600 mcg RAE 600 mcg RAE    
14–18 years 900 mcg RAE 700 mcg RAE 750 mcg RAE 1,200 mcg RAE
19–50 years 900 mcg RAE 700 mcg RAE 770 mcg RAE 1,300 mcg RAE
51+ years 900 mcg RAE 700 mcg RAE    

* Adequate Intake (AI), equivalent to the mean intake of vitamin A in healthy, breastfed infants.

Food:
Concentrations of vitamin A are highest in liver and fish oils. Other sources of preformed vitamin A are milk and eggs, which also include some provitamin A. Most dietary provitamin A comes from leafy green vegetables, orange, red and yellow vegetables, tomato products, fruits, and some vegetable oils. The top sources of provitamin A include carrots, broccoli, cantaloupe, and squash.

Deficiency:
Vitamin A deficiencies are rare in the U.S and mostly found in underdeveloped countries. However, people with cystic fibrosis have pancreatic insufficiency, increasing their risk of vitamin A deficiency due to difficulty absorbing fat.

Cancer:
Because of the role vitamin A plays in regulating cell growth and differentiation, several studies have examined the association between vitamin A and various types of cancer. However, the relationship between serum vitamin A levels or vitamin A supplementation and cancer risk is unclear. The evidence on the relationship between beta-carotene and prostate cancer is mixed. CARET study participants who took daily supplements of beta-carotene and retinyl palmitate had a 35% lower risk of nonaggressive prostate cancer than men not taking the supplements

Age-related macular degeneration:
(AMD) is a major cause of significant vision loss in older people. AMD's etiology is usually unknown, but the cumulative effect of oxidative stress is postulated to play a role. If so, supplements containing carotenoids with antioxidant functions, such as beta-carotene, lutein, and zeaxanthin, might be useful for preventing or treating this condition. Lutein and zeaxanthin, in particular, accumulate in the retina, the tissue in the eye that is damaged by AMD.
The Age-Related Eye Disease Study (AREDS), a large randomized clinical trial, found that participants with some degree of AMD reduced their risk of developing advanced AMD by 25% by taking a daily supplement containing beta-carotene (15 mg), vitamin E (400 IU dl-alpha-tocopheryl acetate), vitamin C (500 mg), zinc (80 mg), and copper (2 mg) for 5 years compared to participants taking a placebo.
A follow-up AREDS2 study confirmed the value of this supplement in reducing the progression of AMD over a median follow-up period of 5 years but found that adding lutein (10 mg) and zeaxanthin (2 mg) or omega-3 fatty acids to the formulation did not confer any additional benefits

Measles:
Vitamin A deficiency is a known risk factor for severe measles. The World Health Organization recommends high oral doses (200,000 IU) of vitamin A for two days for children over age 1 with measles who live in areas with a high prevalence of vitamin A deficiency].
A Cochrane review of eight randomized controlled trials of treatment with vitamin A for children with measles found that 200,000 IU of vitamin A on each of two consecutive days reduced mortality from measles in children younger than 2 and mortality due to pneumonia in children [31]. Vitamin A also reduced the incidence of croup but not pneumonia or diarrhea, although the mean duration of fever, pneumonia, and diarrhea was shorter in children who received vitamin A supplements. A meta-analysis of six high-quality randomized controlled trials of measles treatment also found that two doses of 100,000 IU in infants and 200,000 IU in older children significantly reduced measles mortality

Overdose:
The manifestations of hypervitaminosis A depend on the size and rapidity of the excess intake. The symptoms of hypervitaminosis A following sudden, massive intakes of vitamin A, as with Arctic explorers who ate polar bear liver, are acute. Chronic intakes of excess vitamin A lead to increased intracranial pressure (pseudotumor cerebri), dizziness, nausea, headaches, skin irritation, pain in joints and bones, coma, and even death. Although hypervitaminosis A can be due to excessive dietary intakes, the condition is usually a result of consuming too much preformed vitamin A from supplements or therapeutic retinoids. When people consume too much vitamin A, their tissue levels take a long time to fall after they discontinue their intake, and the resulting liver damage is not always reversible.

The Food and Nutrition Board advises against beta-carotene supplements for the general population, except as a provitamin A source to prevent vitamin A deficiency.

References: Office of Dietary Supplements.

 

How to Defend Yourself Against Breast Cancer.

By Redstone Promotional Communications / Circkles.com.

A friend of mine just found out her best friend has breast cancer. About a week later, she found out her mother has breast cancer, then about a week after that, she found out her dad has cancer. I feel so bad for the poor thing, but it brings to mind just how prevalent cancer is in our world today. Since last month was Breast Cancer Awareness Month, we thought we'd write this month's Health Circkles featured article on natural ways to help woman avoid this increasing disease.

Breast cancer is the most common type of non-skin cancer among women in the United States. The number of new cases of breast cancer in this country in women was estimated to be about 212,600 in 2003 and each year, about 1,300 men are diagnosed with breast cancer. Although fewer African-American women get breast cancer, they are twice as likely to die from it as Caucasian women, according to the American Cancer Society.

To Increase Your Chances Against Breast Cancer:

Your best defense against any type of cancer is to avoid toxins and support your immune system. A study published in 2005 examined the relationship between blood plasma carotenoid levels and found that in women who have been diagnosed with early-stage breast cancer, increased vegetable and fruit intake decreases the likelihood of recurrence.

Go Organic: Fruits and vegetables naturally contain phytochemicals, which both protect the plant from predators as well as act as cancer-fighting antioxidants. The addition of pesticides reduces the need for these natural chemicals, so the plant produces less, thus reducing the level of antioxidant activity in the plant.

Phytoestrogens (plant estrogens). Their estrogen activity, however, is weak, compared to your body’s own estrogen. Phytoestrogens can attach themselves to estrogen receptors on breast and reproductive tissues, and may actually block estrogen from entering cells. This anti-estrogen action could help reduce the risk of hormone-associated cancers (breast, uterine, ovarian and prostate). Phytoestrogens may also help maintain bone density. What’s more, a 2005 study found that 10% flaxseed and its lignan and oil components, alone and in combination, inhibited the growth and spread of human estrogen receptor-negative breast cancer cells in mice.

Cruciferous Vegetables: Scientists are currently exploring the possibility that high intakes of cruciferous vegetables may alter the activity of hormones like estrogen in ways that inhibit the development of hormone-sensitive cancers.

Carotenoids: the yellow, orange, and red pigments in plants. Foods rich in carotenoids include carrots, pumpkins, sweet potatoes, oranges, red peppers, tomatoes, and leafy dark greens such as spinach and kale. Carotenoids generally act as antioxidants, although researchers don’t yet know whether their health benefits are related to their antioxidant activity or to other non-antioxidant activities. The results of large population studies suggest that diets high in carotenoid-rich fruits and vegetables are associated with reduced risk of
cardiovascular diseases and some cancers. That’s why it is best to get carotenoids from food, rather than from supplements. A case in point: High dose beta- carotene supplements have not reduced the risk of cardiovascular diseases or cancers in large research studies. When you cook, adding some fat or oil to carotenoid-containing vegetables lets carotenoids be absorbed better by your body.

Lignans: are naturally occurring compounds found in a wide variety of foods, including seeds (flax, pumpkin, sunflower, poppy); whole grains (rye, oats, barley); bran (wheat, oat, rye); and fruits (particularly berries). Lignans are converted by your intestinal bacteria into two estrogen-like substances known as enterodiol and enterolactone which are phytoestrogens.

Fiber: A 2004 study found that increased fiber intake, independent of a low-fat diet, was associated with reduced blood levels of estrogen in women diagnosed with breast cancer. The reduced estrogen levels may positively affect women with estrogen receptor-positive (ER+) tumors, because ER+ cancer cells need estrogen to grow.

Conflicting Information About Soy: At present, the safety of high intakes of soy isoflavones and other phytoestrogens (plant estrogens) in the diet of breast cancer survivors is an area of considerable debate among scientists and clinicians. No human studies have been conducted to establish whether the weak phytoestrogens in soy fuel cancer growth, or reduce the recurrence of breast cancer. To date, results of cell culture and animal studies have been conflicting. Some have found that soy isoflavones can stimulate the growth of estrogen receptor-positive (ER+) breast cancer cells, however. The effects of high intakes of soy isoflavones in breast cancer survivors who are taking anti-estrogen drugs to prevent recurrence have not been studied, either. So eat soy in moderation.

EFAs: A study published in 1999 found that omega-3 fatty acids (a type of polyunsaturated fat) helped over- weight people burn fat. These omega-3 fatty acids may also benefit the immune system and reduce the risk of metastatic disease. Studies in animal models of cancer indicate that increased intake of the omega-3 fatty acids eicosapen- taenoic acid (EPA) and docosahexaenoic acid (DHA) decreases the occurrence and progression of mammary, prostate, and intestinal tumors

Weight Loss: In addition, being over- weight is associated with elevated estrogen levels and insulin resistance, both of which have been linked to breast cancer.

Non-Processed Foods: Eating more fruits, vegetables, whole grains, legumes (beans and lentils), nuts, and seeds provides a number of health benefits. These plant- based foods are rich in phytochemicals – naturally-occurring compounds that have numerous health-protecting actions. Phytochemicals are not considered essential nutrients (nutrients that must be supplied by the diet because they cannot be produced in sufficient quantities by the body). Nonetheless, they have been shown to provide ample health benefits. Phytochemicals appear to work alone and in combination, and perhaps in conjunction, with vitamins and other nutrients in food to prevent, halt, or lessen disease. To get the most phytochemicals from food, try to eat whole foods (those that are minimally and simply processed and prepared before eating), rather than take supplements. Whole foods retain more of their original nutrients than their processed counterparts. What’s more, our bodies can use the nutrition from whole foods better than from processed foods. The more processed foods are, the less likely they are to contribute to our health. Whole foods retain more of their original nutrients.

Phytochemicals are often found in the pigments of fruits and vegetables, so eating brighter colored varieties may have more benefits. There are, how- ever, several phytochemicals present in colorless or less colorful fruits and vegetables, too – for example, onions and corn. By eating a wide variety of fruits and vegetables, you can make sure that you are getting as many different nutrients as possible.

If you need 2,000 calories a day to maintain your weight and health, aim for at least nine servings (4 1/2 cups) a day.

Tips for increasing fruit and vegetable intake:

• Prepare your plate with no more than 1/3 meat and dairy; fill the rest with fruits, vegetables, and whole grains.

• Choose a variety of fruits and vegetables and include as many phytochemical- rich dark-green, leafy vegetables; yellow, orange, red and purple fruits and vegetables; cooked tomatoes; and citrus fruits as possible.

• Try new things – break out and choose one new fruit or vegetable each week.

• Eat 2-3 meatless meals each week.

• Sprinkle fresh herbs and spices such as garlic, ginger, parsley, cilantro and turmeric root to your foods.

• Try making more nutritious baked goods by incorporating fresh fruits, vegetables, nuts and seeds to the batter.

Eat more whole foods, and fewer processed foods. Tips for eating more whole foods:

• Try to cook from scratch when possible, and never overcook vegetables.
Remember that carotenoids, the phytochemicals found primarily in red, yellow, and orange vegetables and fruits, as well as spinach, collard greens and kale, are best absorbed with fat in a meal. Chopping, pureeing, and cooking carotenoid-containing vegetables in oil generally helps your body better absorb the carotenoids they contain).

• Eat whole fruits instead of drinking fruit juices.

• Replace white rice, bread, and pasta with brown rice and whole-grain products

• Choose whole-grain cereals for breakfast.

•Snack on raw vegetables instead of chips, crackers, or chocolate bars.

•Substitute legumes for meat two to three times per week in chili and soups.

• Experiment with international dishes (such as Indian or Middle Eastern) that use whole grains and legumes as part of the main meal (as in Indian dahls) or in salads (for example, tabbouleh). * Each serving provides 30-60 mg of soy isoflavones.

•Avoid the high levels of isolated soy isoflavones (often listed as “soy protein isolate”) that are found in some protein supplements or powders. If you want to add a liquid meal supplement to your diet, ask a registered dietitian to recommend one that suits your needs and taste. High levels of soy isoflavones may raise the risk of breast cancer in post-menopausal women and interfere with the action of anti-estrogen drugs.

References: God’s Love We Deliver. Nutritional Tips for Breast Cancer Patients.

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HOME REMEDIES: Cracked Heels.

People often ask us for a remedy for cracked heels because it's such a difficult area to find a moisturizer that works, and if the skin becomes cracked enough, it can hurt. The best, and pretty much only remedy, we have found for this persistent problem is to apply something that's thicker and stays on longer than lotions and it's best to apply it at night right before you go to bed. Some people even put socks on their feet after applying a salve, but this almost seems to defeat (no pun intended) the purpose since the socks absorb the salve more than the feet do.

Our solution? Apply a salve that is also absorbable to the skin, such as those that use shea butter or coconut butter to your heels just as you climb into bed. That way it has time to soak in since you won't be wearing any socks or shoes for a while. Reapply for 2-3 consecutive days and you should notice a big difference in the softness of your heels. Since it is on your skin for so long and is therefore soaking into your skin and bloodstream, make sure to use a salve made only with organic ingredients.

If your feet are so cracked they are painful, soak them in a bucket of warm water with Epsom salts for about a half hour before bed time - like when you are sitting down watching t.v. Then apply the salves as mentioned above.

 

HERBS:

How to use herbs for maximum benefit.  Short and sweet descriptions and uses written by our on-staff Nutritional Herbalist.  Always remember that herbs should be treated as a medicine. Almost all of our modern-day medicines are derived from compounds found in herbs and plants. If you have not used a particular herb before, try a half dose at first to make sure you do not have an unfavorable reaction to it.

Dandelion Taraxacum officinale.

Medicinal Properties: A kidney cleanser and diuretic predominately, it is used to improve digestion, stimulate the liver, reduce swelling, treat gallstones, jaundice, cirrhosis, chronic joint and skin complaints, gout, acne, psoriasis, edema associated with high blood pressure, urinary disorders, and in Chinese medicine for breast and lung tumors, mastitis, abscesses, hepatitis, urinary tract infections and snakebite.

And yet so many people poison this beneficial plant because they don't know about its medicinal properties or how to use it.

How to Use: Drink a tea or apply externally as a poultice. Dandelion root has been roasted and used as a coffee substitute although large root can be somewhat bitter, when roasted they have a slightly chocolate taste. Not to exceed 2-3 cups of tea a week.

Dandelion greens can be steamed and eaten like any leafy green, but it's advisable to only use the young, small leaves that come out early in the spring as they will be a little less bitter. However, it is the bitter herb quality that gives them their digestive benefits. You've heard of bitters? Bitter tasting plants and herbs are a digestive aid.

And then there is dandelion wine, something many settlers used to make at home. When mixed with other berries or fruit to make the wine, you can disguise the often bitter taste of the dandelion greens and flowers used to make wine.

How To Roast Dandelion Root:

Dig up the plants in the spring. The bigger the rosette of leaves, the bigger the root and only the bigger roots are worth all the trouble.
Soak the roots in a bucket of water to loosen the dirt on them, scrub them clean and let them dry slightly overnight. Chop them up in a coffee grinder until they are fine enough to use as tea. Don't let the roots dry too long before you grind them up or they will be too hard to grind and may break the blade in your grinder.
One ground to the consistency you want, spread them out on a cookie sheet and slow roast them in a 300º oven for 2-3 hours or until they become a dark brown. For the best "chocolate-like" flavor, roast the root until they are as dark as they can get without being burnt.

Parts Used: Leaves, root, flowers.

Growing: We all know where to find this annoying "weed", but you may think differently about this plant next time you go to pull one or spray it; just remember all its good qualities listed above.

Some Herb Basics: Most herbs work better on an empty stomach. A few exceptions are garlic, goldenseal and cayenne due to stomach upset. Herbs work in a cumulative fashion meaning they are not a "one dose wonder." They need to build up in the system a little, usually within 2-3 doses, before any real affect can be noticed. Fresh herbs always work better than old herbs and science is always proving the fact that a whole herb usually is more effective than one isolated compound of that herb.

 

FOODS THAT HEAL:

Do you know what foods will give you more energy, calm your nerves, act as an anti-inflammatory, help prevent cancers, or help you lose weight? Hopefully this column will help you to have a better understanding of food and its healing properties. The best diet for optimal health is a wide variation of foods, plenty of fresh fruits and vegetables and minimally cooked whole foods. Sweets, fatty foods, meat, dairy and carbs in moderation.

Celery:

Therapeutic Properties: Celery contains good roughage and as such, it benefits digestion and the colon. It contains several anti-cancer compounds and is good for high blood pressure. Best eaten raw for medicinal value, celery is also has a cleansing property to it.
Sodium is needed in the body in order to keep calcium liquid and the sodium in celery is very good for this as it is in a natural form that the body can assimilate well. Counteracts acidosis.

Acid or Alkaline: Alkaline

Significant Nutrients: Rich in sodium, potassium, magnesium and necessary natural chlorine.

Phytoestrogen? No.

Become a Circkles subcriber and join our Recipe of the Month Club for ways to incorporate Foods That Heal into your meals and get our latest recipes sent to you automatically.

You can find more herbs and home remedies in The Circkles Hangout under the Main Menu. (Sorry, you must be a subscriber of Circkles.com.)

 

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November 2013

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"The Doctor of the future will give no medicine but will interest his patients in the care of the human frame, in diet, and in the cause and prevention of disease."
~Thomas Edison
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