Lipids (fats)                                            in oats, peas, beans, apples, citrus fruits,
                                                         carrots, barley and psyllium.
Lipids are composed of long hydrocarbon                 Insoluble fiber promotes the movement
chains. Lipid molecules hold a large amount of           of material through your digestive system
energy and are energy storage molecules.                 and increases stool bulk, so it can be of
Lipids are generally esters of fatty acids and           benefit to those who struggle with
are building blocks of biological membranes.             constipation or irregular stools. Whole-
Most of the lipids have a polar head and non-            wheat flour, wheat bran, nuts, beans and
polar tail. Fatty acids can be unsaturated and           vegetables, such as cauliflower, green
saturated fatty acids. e.g. oils, fats,                  beans and potatoes, are good sources of
phospholipids, glycolipids, etc.                         insoluble fiber.
Lipids present in biological membranes are of
                                                     Vitamin
three classes based on the type of hydrophilic
head present:                                           A vitamin is defined as an organic
                                                         compound and a vital nutrient that an
   Glycolipids are lipids whose head contains           organism requires in limited amounts.
    oligosaccharides with 1-15 saccharide
                                                        A compound is called a vitamin when it
    residues.
                                                         cannot be synthesized in sufficient
   Phospholipids contain a positively charged           quantities by an organism, and must be
    head which are linked to the negatively              obtained from the diet.
    charged phosphate groups.
                                                        Thus, each "vitamin" refers to a number of
   Sterols, whose head contain a steroid ring.          vitamer compounds that all show the
    Example steroid.                                     biological activity associated with a
Roughage or Dietary Fiber or Bulk                        particular vitamin.
                                                        There are two types of vitamins: fat-
   It includes the parts of plant foods your            soluble and water-soluble.
    body can"t digest or absorb.                        Fat-soluble (Vitamins A, D, E, and K)
   It passes relatively intact through your             vitamins are stored in your fat cells,
    stomach, small intestine and colon and out           consequently requiring fat in order to be
    of your body.                                        absorbed.
   Fiber is commonly classified as soluble,            Water-soluble vitamins (Vitamin B & C)
    which dissolves in water, or insoluble,              are not stored in your body; therefore, they
    which doesn"t dissolve.                              need to be replenished daily.
   Soluble fiber dissolves in water to form a
    gel-like material. It can help lower blood
    cholesterol and glucose levels. It is found
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