Natural sources of vitamin D

Diet is not a major source of vitamin D. Perfectly reasonably and well balanced diet may not supply the amount required to prevent deficiency.

Only a few food sources naturally contain appreciable sources of vitamin D3 that have an impact on dietary intake: fish, fish liver, fish liver oil, fatty fish, mushroom, egg yolks and beef liver.

Cod liver oil is the best source of vitamin D. Salmon contains a fair amount of vitamin D; 3 ounces of salmon had about 800 IU of vitamin D. Fatty fish represents the richest natural sources of vitamin D commonly consumed in North America.

Vitamin D is also presents in small quantities in vegetables, meat and egg yolk. Mushrooms are the only vegan source of vitamin D. This form is vitamin D2.

The main food sources are those to which crystalline vitamin D has been added. Milk, because it is commonly used, has proved to be the most practical carrier. Milk, whether nonfat, reduced fat, or whole, provides about 100 IU of vitamin D per ounce glass, and that’s after it has been fortified with vitamin D.

The most efficient source of the vitamin is not a food at all, but exposure to sunlight, which transforms a related pro-vitamin substance in the skin into a substance which the kidney can change into active vitamin D. 

The sun is the major source of vitamin D. Sunlight, in the form of ultraviolet-B radiation, providing 90-100% of the requirement for most of the people who are exposed to adequate sunlight.
Natural sources of vitamin D

Calcium in human diet

Calcium is found in dairy foods, salmon (with bones), sardines, seafood and dark green leafy vegetables. Food sources include almonds, asparagus, blackstrap molasses, brewer’s yeast, broccoli, buttermilk, cabbage, carobs, cheese, collards, dandelion green, dulse, figs, filberts, goat’s milk, kale, kelp, milk, mustard greens, oats, prunes, sesame seeds, soybeans tofu, turnip greens, watercress, whey and yogurt.

 Herbs that contains calcium include alfalfa, burdock root, cayenne, chamomile, chickweed, chicory, dandelion, eyebright, fennel seed, fenugreek, flaxseed, hops, horsetails, kelp, lemongrass, mullein, nettle, oat straw, paprika, parsley, peppermint, plantain, raspberry leaves, red clover, rose hips, shepherd’s purse, violet leaves, yarrow, and yellow dock.

 A diet that is high in protein, fat and/or sugar affects calcium uptake. The average American diets of meats, refined grains, and softdrinks leads to increase excretion of calcium. Consuming alcoholic beverages, coffee, junk foods, excess salt, and/or white flour also leads to the loss of calcium by the body.

A diet based on foods such as vegetables, fruits and wholesome grains, which contain significant amounts of calcium but lower amounts of phosphorus, is preferable.

Oxalic acid (found in almonds, beet greens, cashews, chard, cocoa, soybeans and spinach) interferes with calcium absorption by binding with it in the intestines and producing insoluble salts that cannot be absorbed.

The normal consumption of foods containing oxalic acids should not pose a problem, but overindulgence in these foods inhibits the absorption of calcium. Oxalic acid can also combine with calcium to form calcium-oxalate kidney stones. However, that taking magnesium and potassium supplements can prevent the formation of this types of stone.
Calcium in human diet

Saturated fat in food

Saturated fats mainly found in animal foods – meats, whole milk, and cheese. Some vegetable fats such as coconut and palm and hydrogenated fats provide smaller amounts of saturated fats.

Coconut oil contains as much as 92 percent saturated fats – more that any other oil, including beef fat and lard.

In the 1950s and 1960s when saturated fats was first being associated with elevated cholesterol, researchers began looking for other effects caused by saturated fat.

High intakes of saturated fats contribute most of high blood low density lipoprotein LDL cholesterol. It contributed to heart disease, obesity and other health problems.

Most notable among the saturated fatty acids that raise blood cholesterol are lauric, myristic and palmitic acids.

A fatty acid molecule that has two hydrogen atoms attacked to each carbon is said to be ‘saturated’ with hydrogen because it is holding all the hydrogen atoms it possibly can. This fatty acid is called a saturated fat. 

Generally foods that high in saturated fats content are solid at room temperature.
Saturated fat in food

Calcium in Human Body

Calcium is the most abundant divalent cation of the body, representing about 1.5% to 2 % of total body weight.

Calcium in the body roses from an average of 24 grams at birth to about 1300 grams at maturity.

Over 99% of the total calcium of the body located in the bones, where it accounts for 39% of the total body bone mineral content and in the teeth, mostly as hydroxyapatite.

Physical FunctionStructural component of bones and teeth; role in intracellular and hormonal secretion regulation, muscle contraction, blood clotting, and activation of some enzyme systems.

The calcium in bones serves as a reservoir for calcium that is needed throughout the body.

Calcium also is the key factor in normal transmission of nerve impulses. The movement of calcium into nerve cells triggers the release of neurotransmitter at the junction between nerves.

Deficiency symptoms
The symptoms of calcium deficiency includes rickets, osteomalacia, osteoporosis, scurvy, tetany, parathyroid hyperplasia, stunted growth, laryngospasm.

Deficiency of calcium lowers the body resistance and for the children become as easy prey to respiratory and intestinal infections.

Poor calcium intake affects mostly bone and muscle. Rickets occurs in children when the amount of calcium accretion per unit of bone matrix is deficient.

Hypocalcemia may result in tetany, a condition characterized by intermittent muscle contractions that fail to relax, especially in muscles of the arms and legs.

Food sourcesCalcium is present in foods and dietary supplements as relatively insoluble salts.

Food sources of calcium include milk, milk products, sardines, clams, oysters, turnip greens, broccoli, legumes and dried fruits.

Majority of dietary calcium in industrialized countries comes from milk products.

When substantial amounts of grains are consumed, for like breads or as maize, these can be important sources, although the calcium in cereals rends to be less bioavailable than that in dairy products.
Calcium in Human Body

Food sources of protein

During digestion, large molecules of proteins are broken down into simpler units called amino acids.

Amino acids are necessary for the synthesis of complete body proteins and many others tissue constituent.

Proteins are described as essential and nonessential proteins or amino acids. The human body requires approximately 22 amino acids in specific patterns for the synthesis of its proteins.

All the essential amino acids must be present simultaneously in the diet in order for the other amino acids to be utilized – otherwise, the body remains in negative nitrogen balance.

A lack of vital proteins in the body can cause problems ranging from indigestion to depression to stunted growth.

The body can make only 13 of the amino acids -- these are known as the nonessential amino acids.

They are called non-essential because the body can make them and does not need to get them from the diet.

The nine of these amino acids can be produced are called essential amino acids, and they must be supplied in the diet.

They are methionine, threonine, tryptophan, leucine, isoleucine, lysine, valine, phenylalanine and histidine.

If the protein in a food supplies enough of the essential amino acids, it is called a complete protein.

If the protein of a food does not supply all the essential amino acids, it is called an incomplete protein.

All meat and other animal products are sources of complete proteins. Spirulina contains all the essential amino acids. Soy comes close to being a complete plant protein.

These include beef, lamb, pork, poultry, fish, shellfish, eggs, milk, and milk products.

Protein in foods (such as grains, fruits, and vegetables) are either low, incomplete protein or lack one of the essential amino acids. These food sources are considered incomplete proteins.

To obtain a complete protein form incomplete protein foods, one must combine them carefully so that those foods that are low or missing an essential amino acid will be balanced by another food that supplies that amino acid.
Food sources of protein