Showing food fact sheet for wheat

Wholesome Wheat

Wholesome Wheat

Wheat
Figure 1. Picture of wheat
(image: http://spiritualityhealth.com/articles/wheat-belly)
Wheat grain
Figure 2. Detail of wheat grain
image: http://www.thecookingmentor.com/cooking-basics/
cereals-grains/

Alberta wouldn't be the same without its rolling fields of golden wheat, and neither would our diets! From breads and cakes to pasta and cereal, wheat in its many forms is a true staple. As Canadians, we sit near the top of global production, ranking 6th in the world [FAO]. But the history of wheat as a major food crop dates back to 10,000 years ago, where it was discovered as a food in what is now south-eastern Turkey, gradually spreading to the rest of the world [Shewry, Heun]. Scientifically known as Triticum, wheat was first processed into flour by using a mortar and pestle, but now goes through a more modern milling process [Dexter]. The most valuable part of the wheat grain is the starchy endosperm, which makes up the majority of the kernel and is processed into flour [Catterall]. Because we're always trying to figure out how to best access the endosperm, sometimes we forget the importance of both the wheat germ (the embryo, what nourishes the growing wheat plant) and the wheat bran (outer layer of the wheat kernel). In fact, contained within these two parts of the wheat grain are most of wheat's beneficial nutrients, which is why "whole grain" really does matter! Wheat has many health properties that you might not know about, such as preventing heart disease, diabetes, cancer, improving immune function, and even helping with weight management. Loaded with protein, vitamins and many minerals, it's easy to understand why wheat is so wonderful!

Vitamins in Wheat

Pantothenic acid
Figure 3. Structural diagram of pantothenic acid

Wheat is rich in B-complex vitamins (B1, B3, B5, B6 and folate), that are found in all parts of the grain [USDA]. These vitamins are used throughout the body, primarily in energy metabolism. The most common form of vitamin B1 (or thiamin) in the body is as the cofactor cocarboxylase (or TPP) [McDowell]. TPP plays a role in the citric acid cycle (as a cofactor to pyruvate dehydrogenase), used to generate energy from carbohydrates. Thiamin and its derivatives (TPP, Thiamin triphosphate or TTP and thiamin monophosphate or TMP) are important in nerve function. The mechanism is unclear, but likely to do with nerve transmission. When nerves are stimulated, levels of TPP and TTP decrease, free thiamin and TMP are released into fluid surrounding the nerve. The Several neurological disease are related to thiamin deficiency, including beriberi and Wernicke's syndrome (associated with alcoholism) [McDowell]. vitamin B3 (or niacin) is used in many coenzymes integral to energy metabolism (NAD and its derivatives), and is beneficial for cardiovascular health, lowering LDL cholesterol and raising HDL cholesterol [Higdon]. Another vitamin in wheat is vitamin B5 (or pantothenic acid). Vitamin B5 is required for the ubiquitous coenzyme A synthesis - a coenzyme used in fatty acid metabolism (both oxidation and synthesis) and energy generation (in the citric acid cycle) [Daly]. vitamin B6 is a group of several similar compounds (including pyridoxine, pyridoxal, and pyridoxamine), used in over 100 enzymes [Erdman]! They can be found maintaining DNA and in the metabolism of carbohydrates, fats and proteins . And finally, there is folate (or vitamin B9). Folate is a supplement that all pregnant women require to prevent their babies from developing spinal cord problems (such as spina bifida or acephaly) and cognitive birth defects [Daly]. Folate is essential for the growth of new cells (especially red blood cells), and is also good for the heart, by breaking down homocysteine, an amino acid that increases risk of the disease [Wang]. Finally, folate can reduce side effects of certain arthritis medications and chemotherapies by replenishing diminished folate stores [Shea, Nadhananan].
Bottom line: The B-complex vitamins found in wheat are essential to digestion and energy metabolism.

Minerals in Wheat

Prostacyclin
Figure 4. Picture of prostacyclin

Wheat naturally contains a host of amazing minerals - such as manganese, phosphorus, magnesium, zinc, and iron [USDA]! In recent years, farmers have fortified their wheat to have even higher mineral amounts, so eating a slice of bread can be just as good as taking your supplements! Manganese is a component of many enzymes that are used in metabolic pathways. These enzymes are found in protein, carbohydrate and cholesterol metabolisms. A manganese deficiency has been implicated in many bone-related problems, and some metabolic issues [National Research Council]. With the hefty dose of manganese in wheat comes anti-aging effects such as stronger cartilage and cell membranes, and prevention against cancer [Fardet]. Like calcium, phosphorus is very abundant in the human body and is needed to keep teeth and bones strong and healthy. It is important in memory, growth, tissue repair, pH balancing, can be used to treat kidney stones, and much more [Loghman-Adham, Fardet]. Phosphorus is used throughout the body, often in a phosphate - a naturally occurring compound. Phosphates are important in energy storage, nucleic acids and membranes. Phosphorus and calcium form hydroxyapatite, which is found in bones and teeth [Uenishi]. Yet another mineral responsible for bone health that is found in wheat is magnesium, which humans are commonly deficient in. Magnesium is important in vital body functions, such as regulating blood pressure, nervous and muscular equilibrium [Kass]. The body balances mineral concentrations to ensure proper functioning, and when the body attempts to balance between magnesium and calcium, prostacyclin is released, causing vasodilation (blood vessel muscle relaxation - lowering blood pressure) [Rude]. Like magnesium, zinc is also an essential mineral for the human body that's important for blood pressure, nerve function and mental health. Contained in almost every tissue in our bodies, zinc is important for brain development and function, and has cell-signalling roles within various tissues [Walsh]. Associated with over 300 enzymes in the human body, zinc is critical in many processes such as immune function, homeostasis of cell processes, and metabolism [Frederickson]. It is an ionic signalling molecule, which means that it can move among various membrane channels and bind with proteins that depend on zinc [Frederickson, Yu]. Some of these many proteins include the DNA-binding proteins TFIIA, GAL4, g32P, the protein kinase C that is important in signal transduction pathways, and neurotransmitter receptor proteins gamma-aminobutyric acid (GABA) and N-methyl-D-aspartate (NMDA), which are important for the passing along signals in the brain [Walsh]. Finally, it's a commonly known fact that iron is very important in normal body functions, especially because it is an important part of the hemoglobin protein, which carries oxygen in the blood. Without enough iron, your body's ability to transport oxygen is reduced, and you're susceptible to anemia. Symptoms of this disease typically include tiredness, dizziness, and weakness.
Bottom Line: Ditch your supplements and eat wheat! It's rich in all sorts of minerals, making sure your body stays balanced and healthy.

Wheat, Whole Grains and Weight Management

A whole grain, as defined by the FDA, is the "intact, ground, cracked or flaked fruit of the grain whose principal components, the starchy endosperm, germ and bran, are present in the same relative proportions as they exist in the intact grain" [FDA/Jonnalagadda]. In other words, whole grain is the commercial equivalent of the grain that is grown on a plant. Refined grains often leave out parts of the bran and germ, reducing the nutritional content of the grain [Jonnalagadda]. An increased consumption of whole grains has been shown to have many benefits, some that are not in refined grains [Okarter/Mckeown 2009].
Hooray for whole wheat! Body mass index and body fat were lowered following consumption of whole grains across several studies [Mckeown 2009/Harland//Newby/Koh-Banerjee]. This does not make whole grain foodstuffs weight loss wonder drugs; research around whole grains and weight loss has been conflicting [Koh-Banerjee/Kristensen]. The mechanisms surrounding fat reducing effects of whole grain consumption are still unknown [Jonnalagadda]. Researchers suggest that it may have to do with a feeling of fullness (satiety) after eating foods such as whole grain wheat [Holt]. In this sense, wheat is beneficial for people with high fat levels. Yet, wheat is controversial in some circles. Recently, people have blamed wheat for causing the uptick in obesity across developed nations. That just one food could cause an obesity epidemic is highly unlikely, as there are many lifestyle choices that impact health. Scientists have debunked this claim, due to several factors, including the rise of obesity in places where wheat-based foods are not readily consumed, and wheat being a staple food for thousands of years prior to the present obesity epidemic [Brouns]. Furthermore, research indicates whole grains have a protective role against obesity (and metabolic syndrome), likely as a result of the fermentation of insoluble fiber that creates butyric acid [Fardet/Björck/Harris].
Bottom Line: Eat whole grains! They will improve your nutrition and protect you from obesity!

Whole Wheat and Heart Health

Heart
Figure 5. A heart weightlifting
(image: http://www.themorningstrut.com/
images/Heart-Health.jpg)
Cardiovascular disease (CVD) is the leading cause of death in the world, resulting in approximately 17 million deaths annually [WHO]. CVD is often a result of lifestyle choices, including dietary decisions. Whole grain foods are a good choice for heart-conscious folks: they have been shown to lower the risk of CVD in many epidemiological studies [Jonnalagadda]! Researchers have said that "the intake of wholegrain foods clearly protects against heart disease and stroke", and that a high intake of whole grain food results in a lower risk of cardiovascular disease, including stroke and heart attacks [Flight, Mellen]. This research is supported by studies that found an inverse association between consumption of whole grains and the risk of arterial buildups that can cause heart attacks [Jacobs/Anderson]. In one such case, whole grain consumption prevented the progression of coronary artery disease in older women [Erkkilä]. In another study, the consumption of whole grains reduced the incidence of hypertension (high blood pressure) in men, possibly due to the bran [Flint]. Possible mechanisms of action include slightly lowering blood glucose and the bacteria-benefiting prebiotic effect of compounds in wheat [Harris].
It's also possible that one specific part of the wheat bran, called the aleurone layer, can help prevent heart disease because it decreases "bad" cholesterol (LDL). Studies show that consumption of wheat with the aleurone layer will increase plasma betaine and will decrease the amount of homocysteine and LDL cholesterol, through the betaine-homocysteine methyltransferase pathway. This pathway requires betaine by consuming betaine or choline (which is transformed to betaine). High levels of homocysteine are known to increase the risk for cardiovascular disease and even Alzheimer's disease [Zeisel]. Various studies have found that betaine is key in lowering cholesterol [Price], and that wheat betaine is faster at reducing LDL cholesterol than any betaine supplements [Atkinson]! This decrease might also be quickened by other nutrients in the wheat: specifically folate and vitamin B12 [Atkinson].
Bottom line: Keep your heart ticking with whole grain wheat!

Anti-Cancer Phenols

Lignans are a type of polyphenolic compound found in plants, and wheat is no exception! Common lignans in wheat include secoisolariciresinol (SECO), lariciresinol (LARI), pinoresinol (PINO), matairesinol (MATA), and hydroxymatairesinol (HMR) [Cukelj]. Their anticancer effects stem from the fact that lignans are phytoestrogens, which means that they can mimic estrogen. But before they can do this, the plant lignans change into to mammalian lignans (enterodiol and enterolactone) through fermentation by bacteria in the colon [Begum,Heinonen]. Enterolactone is able to activate the estrogen receptors ER-alpha and ER-beta, inducing the estrogen responsive element (ERE), which contains reporter genes that fool the body into thinking that there is actually estrogen in the receptors [Penttinen]. This mimicry slows down the proliferation of the breast cancer cell MCF-7, which is sensitive to estrogen levels [Saarinen]. In many types of cancer (like prostate, breast, and colon), higher estrogen levels are thought to increase cancer cell growth, and so lignans may play a big role in preventing these diseases [Byland, Qu]. Interestingly enough, lignans can also help prevent cancer by inhibiting enzymes linked to proliferation of cancer cells, such as 3-beta-hydroxysteroid dehydrogenase, 5-alpha-reductase, phenol sulfatase, topoisomerase I and II, and aromatase [Adlercreutz]. One such enzyme, aromatase, is the synthesizer of estrogen[Chen]. Enterolactone can bind to aromatase active sites and inhibit the production of estrogen, reducing risk of breast and prostate cancer [Adlercreutz].

Ferulic acid
Figure 6. Structural diagram of ferulic acid
But the lignan in wheat isn't the only compound that helps fight against cancer! Other important nutrients found in wheat also have strong anti-cancer properties, such as ferulic and caffeic acids. Both of these hydroxy-cinnamic acids are found in the wheat bran, where they make up cell walls and play an important role in protecting the seed [Slavin, Liu]. Ferulic acid, the most dominant hydroxycinnamic acid in wheat, has a variety of health benefits, but the most important benefit is how it inhibits cancer [Li]. Two ways it does this are: 1) by promoting the production of apoptosis-causing enzymes (caspase), and 2) increasing ROS (reactive oxygen species like superoxide) levels in an effort to kill cancer cells, and inhibit cancer growth [Slavin, Alias, Karthikeyan, Peng, Prabhakar].
Another important hydroxycinnamic, caffeic acid (not related to caffeine) has a number of beneficial anti-cancer properties. In one recent study, caffeic acid inhibited the B-cell lymphoma (Bcl-2) protein associated with apoptosis regulation, which led to a molecular domino effect that eventually killed the cancerous cells [Chang]. In another, caffeic acid was shown to have the same apoptosis-inducing effect on colon cancer cells [Jaganathan]. Plus, caffeic acid can unleash a barrage of cellularly-produced cancer-killing compounds, like reactive oxygen species (ROS) that damage a cancer cell's DNA and induce apoptosis [Rajendra]. Caffeic acid also has some very clear anti-inflammatory effects[de Cunha]. Caffeic acid will hunt down harmful chemicals in an effort to reduce inflammation, inhibit inflammatory genes, as well as reducing damage created by inflammation [de Cunha/Zhang/Yang].
Bottom line: Way to go wheat! When you eat the whole grain, anti-cancer benefits come straight from the bran!

Immunity-Boosting

Who knew that wheat could be so good for keeping your body disease-free? Two components of the fiber found in wheat bran have been shown to have anti-inflammatory properties. The polysaccharide beta-glucan has been shown to be beneficial because it initiates immune responses such as phagocytosis (when one cell "eats" another cell). Beta-glucan binds to the receptors of lymphocytes, specifically, membrane receptor dectin-1 [Brown]. These receptors are responsible for stimulating T-cell proliferation. This stimulation kickstarts the antimicrobial effects of beta-glucan, such as the phagocytosis of pathogens [Dritz]. But there are other parts of wheat that make it helpful for your immune system as well!

Dextrin
Figure 7. Structural diagram of dextrin
Prebiotics are nondigestible fibers that benefit microorganisms in the colon, they include inulin, fructooligosaccharides (FOS) and galactooligosaccharides (GOS) [Gibson/Roberfroid]. To be a prebiotic, a food ingredient must be "a selectively fermented ingredient that allows specific changes, both in the composition and/or activity in the gastrointestinal microflora that confers benefits upon host well-being and health" [Roberfroid]. These strict criteria mean that only a few types of sugars are considered prebiotics [Fardet]. Surprisingly, wheat is the greatest source of prebiotics for most Americans [Moshfegh]! The prebiotics in wheat include dextrin, inulin and fructan derivatives (FOS) [Slavin/van Loo]. When in the gut, prebiotics serve as food for specific bacteria, namely bifidobacteria and lactobacilli [Costabile]. When fermented, it has been shown that prebiotics are converted to short-chain fatty acids (SCFA's) such as butyrate, which cause a variety of immune-system optimizing benefits [Schley]! These include: 1) Butyrate serving as an energy source for intestinal epithelial cells, which frees up the glutamine (that usually feeds them) for immune functions like lymphocyte and cytokine production [Calder, Schley]. 2) Increased butyrate production was found to increase proportions of T-regulator cells (which maintain immune system homeostasis), as well as decrease the production of inflammatory IFN-gamma cytokines [Cohn, Klampfer]. 3) Butyrate reduces inflammation through activating peroxisome proliferator-activated receptor gamma (PPAR-gamma), which is responsible for suppressing proinflammatory pathways in the gut (such as STAT, AP-1, and NF-ΚB), which play a role in diseases such as inflammatory bowel disease (IBD) [Inan, Vieira].
Bottom line: Our daily bread can help in the fight against disease and inflammation!


References

Introduction

Vitamins in Wheat

Minerals in Wheat

Wheat, Whole Grains and Weight Management

Wheat and Cardiovascular Disease

Anti-cancer

Immunity boosting

Diabetes