Vitamin A, The Good & The Bad 0

Humans require vitamin A for proper Immune function, Good vision, Reproduction and Tissue growth. However, taking vitamin A supplements in excess may lead to headache symptoms, as well as, Birth defects.

Humans get vitamin A from Plants and Animal produce.

While Animals produce, provide humans with already formed sources of vitamin A, mainly retinol, and retinyl esters, Plants produce, provide humans with vitamin A precursors only, known as the Carotenoids.

Biochemistry:

Plant precursors (carotenoids).

The red-yellow pigments, found in vegetables and fruits, are vitamin A precursors. The most important precursor is Beta-carotene.

Intestinal digestion, releases free beta-carotene, which then needs to mix with bile, and other products of fat digestion to form liquid micelles, that allow the beta-carotene to cross into the intestinal mucosa.

In the intestinal mucosa, the beta-carotene is cleaved into 2 vitamin A aldehydes: retinal, (by an enzyme Beta-carotene dioxygenase)

The enzyme, retinaldehyde dehydrogenase add Hydrogen atoms to the aldehyde, retinal, converting it to the alcohol form, Retinol.

The Retinol, and remaining beta-carotenes are packaged into Chylomicrons and transported into the liver. The liver has the capability to convert the remaining beta-carotene into retinol, too.

In the liver, retinol is stored as Retinyl esters. Retinyl esters are de-esterified into retinol, when needed

Not all the beta-carotene in the diet is converted to retinol (vitamin A).

The conversion of beta-carotene to vitamin A decrease as the dietary dose of beta-carotene increases.

On the average, 12mcg of beta-carotene, generates 1mcg of retinol.

PLANT VITAMIN A PRECURSORS:

. Green leafy vegetables, Spinach, Broccoli

. Orange and yellow vegetables, Squash, Carrots, Pumpkin

. Tomato products

. Fruits, Pink Grapefruits, Pawpaw, Mango, Oranges

ANIMAL PRODUCE

Retinol and Retinyl ester are the already formed vitamin A in animal products: Fish, Dairy, and Meat (especially the liver) products.

On the average, there is 1:1 conversion of ingested food Retinol to body Retinol.

1mcg of food retinol generates 1mcg of retinol.

FUNCTIONS OF VITAMIN A

Vitamin A exists in three forms:

Storage form: Retinyl-esters, in the liver (mainly), but also in the lungs and bones

Transportable form: Retinol, which circulates, attached to retinol binding proteins.

Metabolically active form: Retinoic acid. Inside the cells, retinol is converted to retinal which is then reduced to retinoic acid. Retinoic acid binds to receptors to either activate or repress genes transcriptions.

Cytochrome P450 family oxidize retinoic acid to degradable forms.

VITAMIN A AND VISION

Retinol is carried to the retina where it is oxidized to retinal in rod cells. Retinal then combines with the pigment, Opsin, to form rhodopsin in the eye rods.

When a photon of light hit Rhodopsin, it catalyzes the switch of retinal, from –cis to –trans form, and this, initiates signal transmission to the optic nerve and the brain, for us to see objects in dim light.

Night blindness, is due to inadequate supply of retinol to the eye rods, but could also be due to zinc deficiency.

VITAMIN A AND EPITHELIAL CELLS

Vitamin A modulates the transcription of several hundreds of genes.

Vitamin A support cell growth and differentiation. It plays a critical role in the normal functioning of Heart, Kidneys and Lungs.

Vitamin A maintains the integrity and barrier-function of the skin and mucosal lining of the airways, digestive and urinary tracts, against infections. Cell linings protective of tissue surfaces fail to regenerate and differentiate, become flat and pile up keratin. They fail to generate protective secretions and cells required for immunity.

Epithelial tissues become Dry (Xerosis). Dry eyes are common.

Absence of vitamin A from diets has been associated with general susceptibility to infection.

Vitamin A deficiency increases the severity and mortality of infections like Diarrhea and measles.

Vitamin A is required for Sperm development in adult males and in the absence of vitamin A, sperm development is arrested.

VITAMIN A AND HUMAN EMBRYO.

The human embryo, needs a steady and adequate supply of maternal vitamin A, for normal development.

Retinoic acid, via retinoid receptors is involved in pathways that regulate development.

Both the lack and excess of vitamin A during embryonic development results in birth defects.

Vitamin A plays a major role in migration and differentiation of Neurons, during neurodevelopment.

Also, during the 2nd Trimester, low maternal Vitamin A is associated with x3 fold increase in risk if schizophrenia in adult offspring.

Lung development and maturation requires adequate vitamin A maternal diet

VITAMIN A AND MEASLES

Vitamin A deficiency is a risk factor for severe forms of measles infection.

The World Health Organization recommends children aged 1 year and over to take 200000 IU of Vitamin A daily for 2 days, when they develop measles infection. This practice helps prevent pneumonia deaths in children aged less than 2 years who develop measles.

Children deficient in vitamin A, account for half the percentage of kids who develop corneal ulcers with measles.

Half of the children who develop bilateral blindness, after measles infections, have vitamin A deficiency.

Vitamin A deficiency is one of the top causes of preventable blindness in children.

GROUPS AT RISK OF VITAMIN A DEFICIENCY

Serum Retinol level above 1.051micromol/L, marks adequacy.

Serum Retinol level 0.35-1.05micromol/L denotes subclinical deficiency.

Serum Retinol level below 0.35micromol/L is associated with Corneal diseases.

Preterm Infants.

Prematurely born children do not have adequate liver stores of vitamin A.

Vitamin A is required for lung development and maturation.

Vitamin A-deficient preterm infants have increased risk of Eye, Chronic Lung and Bowel diseases.

Infants and Toddlers

Exclusively breastfed infants, of mothers with vitamin A deficiency do not have adequate liver stores for vitamin A. Most kids develop Xerophthalmia after breast feeding.

Pregnant & Lactating Women.

Vitamin A Requirement during pregnancy increases, to support maternal metabolism and fetal growth.

Vitamin A deficiency in pregnant and breast-feeding women, lead to increase morbidity and mortality, for the mother and child. The children born to these women are at risk for Anemia and slower growth and development.

Intestinal Malabsorption

People with cystic fibrosis and other diseases associated with poor bowel absorption, are also at risk of Vitamin A deficiency. The good news is that Vitamin A supplements help to alleviate this problem.

Orlistat, the weight loss medication, decreases absorption of beta carotenes

VITAMIN A TOXICITY.

Vitamin A is stored in the liver when not required, and the levels could pile up readily.

CONVERSION FACTOR:

Plant sources of Beta-carotene, do not lead to vitamin A toxicity. This is because, Nature has a way to reduce the conversion of beta-carotene to retinol, when ingested.

The more beta-carotene you eat, the less is converted to retinol.

The rest of ingested beta-carotene is stored in fat reserves in the body. Even though too much consumption of beta-carotene shall make your palm and skin yellow, you do not develop vitamin A toxicity.

On the average it requires 12mcg of beta-carotene to generate 1mcg of retinol. (12:1conversion factor)

The situation is different when one consumes preformed vitamin A from diet and nutritional supplements.

1mcg of preformed dietary Retinol, (from animal produce) generates 1mcg of retinol in the body. (1:1 conversion).

Unless one has vitamin A deficiency, Vitamin A dietary supplements could be unnecessarily dangerous.

Studies indicate that, taking nutritional supplements like Beta carotene 30mg daily, or Retinyl palmitate 25000IUdaily for 5-8 years increases risk of death from Lung cancer and Heart diseases

Eating fruits and vegetables is more beneficial and superior to dietary vitamin A supplements.

Daily Vitamin A requirements in microgram of Retinol Activity Equivalents (RAE)

. Male Adults & Teenagers: 900 mcg RAE

. Female, Adults & Teenagers:700mcg RAE

. Lactating Females: 1300mcgRAE

. 0-6month: 400mcgRAE/7-12 months:500mcgRAE/1-3 years: 300mcgRAE/4-8years:400mcgRAE/

.9-13 years: 600 mcg RAE

SYMPTOMS OF HEPERVITAMINOSIS A include: Dizziness/Headaches/Bone and Joints pain/Skin irritation

Increased intracranial pressure/Coma/Death.

@2018 Dr Alex K. Sarkodie

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Adverse Health Effects of Plastics 0

In addition to creating safety problems during production, many chemical additives that give plastic products desirable performance properties also have negative environmental and human health effects. These effects include

  • Direct toxicity, as in the cases of lead, cadmium, and mercury
  • Carcinogens, as in the case of diethylhexyl phthalate (DEHP)
  • Endocrine disruption, which can lead to cancers, birth defects, immune system suppression and developmental problems in

Chemical Migration from Plastic Packaging into Contents

People are exposed to these chemicals not only during manufacturing, but also by using plastic packages, because some chemicals migrate from the plastic packaging to the foods they contain. Examples of plastics contaminating food have been reported with most plastic types, including Styrene from polystyrene, plasticizers from PVC, antioxidants from polyethylene, and Acetaldehyde from PET.

Among the factors controlling migration are the chemical structure of the migrants and the nature of the packaged food. In studies cited in Food Additives and Contaminants, LDPE, HDPE, and polypropylene bottles released measurable levels of BHT, Chimassorb 81, Irganox PS 800, Irganix 1076, and Irganox 1010 into their contents of vegetable oil and ethanol. Evidence was also found that acetaldehyde migrated out of PET and into water.

Recommendations

Find alternatives to plastic products whenever possible. Some specific suggestions:

  • Buy food in glass or metal containers; avoid polycarbonate drinking bottles with Bisphenol A
  • Avoid heating food in plastic containers, or storing fatty foods in plastic containers or plastic wrap.
  • Do not give young children plastic teethers or toys
  • Use natural fiber clothing, bedding and furniture
  • Avoid all PVC and Styrene products
Plastic Common Uses Adverse Health Effects
Polyvinylchloride (#3PVC) Food packaging, plastic wrap, containers for toiletries, cosmetics, crib bumpers, floor tiles, pacifiers, shower curtains, toys, water pipes, garden hoses, auto upholstery, inflatable swimming pools Can cause cancer, birth defects, genetic changes, chronic bronchitis, ulcers, skin diseases, deafness, vision failure, indigestion, and liver dysfunction
Phthalates (DEHP, DINP, and others) Softened vinyl products manufactured with phthalates include vinyl clothing, emulsion paint, footwear, printing inks, non-mouthing toys and children’s products, product packaging and food wrap, vinyl flooring, blood bags and tubing, IV containers and components, surgical gloves, breathing tubes, general purpose labware, inhalation masks, many other medical devices Endocrine disruption, linked to asthma, developmental and reporoductive effects. Medical waste with PVC and pthalates is regularly incinerated causing public health effects from the relese of dioxins and mercury, including cancer, birth defects, hormonal changes, declining sperm counts, infertility, endometriosis, and immune system impairment.
Polycarbonate, with Bisphenol A (#7) Water bottles Scientists  have linked very low doses of bisphenol A exposure to cancers, impaired  immune function, early onset of puberty, obesity, diabetes, and  hyperactivity, among other problems (Environment California)
Polystyrene Many food containers for meats, fish, cheeses, yogurt, foam and clear clamshell containers, foam and rigid plates, clear bakery containers, packaging “peanuts”, foam packaging, audio cassette housings, CD cases, disposable cutlery, building insulation, flotation devices, ice buckets, wall tile, paints, serving trays, throw-away hot drink cups, toys Can irritate eyes, nose and throat and can cause dizziness and unconsciousness. Migrates into food and stores in body fat. Elevated rates of lymphatic and hematopoietic cancers for workers.
Polyethelyne (#1 PET) Water and soda bottles, carpet fiber, chewing gum, coffee stirrers, drinking glasses, food containers and wrappers, heat-sealed plastic packaging, kitchenware, plastic bags, squeeze bottles, toys Suspected human carcinogen
Polyester Bedding, clothing, disposable diapers, food packaging, tampons, upholstery Can cause eye and respiratory-tract irritation and acute skin rashes
Urea-formaldehyde Particle board, plywood, building insulation, fabric finishes Formaldehyde is a suspected carcinogen and has been shown to cause birth defects and genetic changes. Inhaling formaldehyde can cause cough, swelling of the throat, watery eyes, breathing problems, headaches, rashes, tiredness
Polyurethane Foam Cushions, mattresses, pillows Bronchitis, coughing, skin and eye problems. Can release toluene diisocyanate which can produce severe lung problems
Acrylic Clothing, blankets, carpets made from acrylic fibers, adhesives, contact lenses, dentures, floor waxes, food preparation equipment, disposable diapers, sanitary napkins, paints Can cause breathing difficulties, vomiting, diarrhea, nausea, weakness, headache and fatigue
Tetrafluoro-
ethelyne
Non-stick coating on cookware, clothes irons, ironing board covers, plumbing and tools Can irritate eyes, nose and throat and can cause breathing difficulties

Sources:

 

ecologycenter.org

Home Remedies for Hiccups 0

We have all been tormented by hiccups at some point in our lives those annoying, involuntary fits that can make it nearly impossible to carry on a conversation, eat a meal or even maintain a train of thought. Most people hiccup four to 60 times per minute during a bout of hiccups, and everyone has a specific, lifelong hiccup pattern.

The average hiccup spell can last from a few minutes to a few hours, but some people suffer from extended episodes that last days, months or even years. Hiccups that last longer than 48 hours are called persistent hiccups,and if they’ve lasted more than a month, you have intractable hiccups.

Both types can cause serious health problems and, in some cases, even death. For many of us, hiccups begin in the womb. The recapitulation theory proposes that fetuses use hiccups in respiration before their lungs are fully developed. This may help explain why premature infants spend up to 2.5 percent of their time hiccuping more than full-term babies.

Hiccup is an involuntary and sudden contraction of the muscles of the diaphragm. Normally, this action is repeated many times. A weird sound (hic) is produced. The sound is because of the epiglottis which closes when air suddenly tries to rush in. Hiccups are not as painful usually, though they can be very irritating at times. When they continue for a long period, they are very irritating.

Hiccups Causes:

  1. If you eat too fast, you can swallow air along with your food and end up
    with a case of the hiccups. Any other practices that might irritate the diaphragm such as eating too much (especially fatty foods) or drinking too much (drunk people hiccup) can make you prone to having hiccups.
  2. In these instances, your stomach, which sits underneath and adjacent to the
    diaphragm, is distended or stretched. Because they occur in relation to
    eating and drinking, hiccups are sometimes thought to be a reflex to protect
    you from choking.
  3. Sobbing or crying – Eating very spicy food,
  4. Consuming very hot food,
  5. Consuming excessive alcohol or soda,
  6. Coughing badly,
  7. Laughing badly.
getty

Scientific Causes of Hiccups:

During normal breathing, we take in air from the mouth and nose, and it flows through the pharynx, past the glottis and into the larynx and trachea, ending in the lungs. The diaphragm, a large muscle between the chest and abdomen, aids this airflow. It moves down when we inhale, and then up when
we exhale. The phrenic nerves control the movement and sensation of the diaphragm. Any irritation to these nerves induces a spasm of the diaphragm. This spasm causes a person to take a short, quick breath that is then interrupted by the closing of the epiglottis (a flap that protects the glottis, the space between the vocal cords). The sudden closing creates the sound we all know as a hiccup.

So, hiccups are the result of diaphragm spasms. But what causes the irritation that leads to the spasm? There are only a few culprits for common hiccups, which usually disappear within a few minutes. One of the main irritants is a full stomach a result of swallowing too much food
or air. A distended stomach pushes against the phrenic nerves of the diaphragm, increasing the possibility of irritation and, therefore, hiccups. A full stomach of spicy food can do double damage hot foods can be especially irritating to those nerves. As any smoker on a bender can tell you, excess
smoking and drinking alcohol can also cause hiccups. A rapid temperature change outside or inside your stomach, from a cold night or a hot beverage, can be irritating enough to induce hiccups. Finally, emotions shock, excitement and stress — can also trigger a hiccup fit. Persistent and intractable hiccups can have more serious causes. There are hundreds, from hysteria to heart attacks, but most fit into one of five categories: central nervous system problems, metabolic problems, nerve irritation, anaesthesia or surgery, and mental health issues. Because these causes are so varied and potentially serious, anyone suffering from hiccups for more than 48 hours should head straight to a doctor.

Home Remedies for Hiccups:

  1. Holding your breath and counting to 10 is one way some people can get rid of their hiccups. Other people say that drinking from the “wrong” side of a glass of water is the way to become hiccup-free.
  2. Putting sugar under your tongue might work.
  3. Pound 5-6 green cardamom. Boil in 2 cups of water. When it boils down to 1
  4. cup remove, sieve and drink while warm.
  5. Drinking water frequently in short durations is also helpful.
  6. Eating a bowl full of yoghurt with a pinch of salt is also a good home remedy.
  7. Tickling the throat with the cotton swab is also helpful.
  8. Drink one ounce of white vinegar.
  9. Sucking crushed ice provides immediate relief
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