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1
Got Food?
Recent Advances in
Food ScienceandTechnology
~~~~~~~~~~~~
An e-book co-authored by the Class of 2013
Massachusetts Academy of Math andScience
~~~~~~~~~~~~
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Chapter 1 Diet and Nutrition 3
Ann Ming Samborski, Amanda Stevens, and Ingrid Marko
Chapter 2 Vitamins and Minerals 19
Barry Biletch, John deRivera, and Aniket Lachyankar
Chapter 3 Food Supplements 31
Patrick Aoude, Julia Knowles, and Derek Wegener
Chapter 4 Diet and Diabetes 44
Nora Murphy and Jay McCowan
Chapter 5 Diet and Heart Disease 55
Arjun Tanguturi and Rebecca Stolarczyk
Chapter 6 Vegetarian and Vegan Diets 62
Dhroova Aiylam and Cameron Root
Chapter 7 Childhood Obesity 70
Emma Hewett, Sierra Harris, Angelica Heeney, and Divya Satishchandra
Chapter 8 Global Food System 82
Ryan Thibodeau., Thomas Devlin, and Abigail Yu
Chapter 9 Green Revolution 94
Michael Andrews, Alexander Lee, and Sahit Mandala
Chapter 10 Food Preservation 105
Adam Carrier, Tony Trakadas, and Katherine McDonough
Chapter 11 GMO Crops 116
Rachel Maillet, Anish Athalye, George Han, and Osi Van Dessel
Chapter 12 Sustainability andFood 130
Dennis Giaya, Eric Williams, and Rohit Satishchandra
Chapter 13 Agriculture, Irrigation, Fertilization, and Pesticides 140
Ryan Fletcher and Aaron Hammond
Chapter 14 Food Additives 148
Naveena Shanmugam, Jacob Grotton, Daniel Huang, and Jeeva Jacob
Chapter 15 Cooking in Developing Countries 164
John Dymek, Deidre DiLiddo, and Mark Guertin
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Chapter 1
Diet and Nutrition
Ingrid Marko, Ann Ming Samborski, and Amanda Stevens
Diet
Societal values intimidate individuals to obtain the ideal physique. Often in order to achieve this, a
healthy lifestyle must be implemented. Unfortunately, such a simple solution is often taken to the
extreme. In fact, there are numerous diet plans on the market that may become a detriment to the lives of
many. Moreover, a sustainable way of life is without a doubt beneficial, but it is important to keep matters
in perspective.
The ever-changing rules of what defines a ―good diet‖ confuse people to the point that they are
uncertain of what foods to consume. There are so many different meal plans in existence that it is almost
impossible to decide on which one to follow. Yet, with the technologyand knowledge of today, it should
be relatively easy for nutritionists to plan out a healthy meal. For instance, Dr. Oz (2011) writes that in
order to be healthy, people must abstain from diet soda and low fat foods because the present processed
sugars are the main contributors to an overweight population. Ultimately, the individual is the greatest
influence because each body works differently due to the dissimilarity among DNA. In fact, protein,
carbohydrates, and lipids satisfy the body enough that it may not require the remaining components to
sustain a healthy state (Liao, 2012).
When it comes to nutrients, the body regulates a certain amount that it needs each day. Skipping
any of these will result in over-consumption of another, which then leads to an unhealthy diet (Liao,
2012). Important substances to consume daily are eggs, nuts, lipids, and similar foods. Even drinking
whole milk and wine are a necessity according to Dr. Oz. It is overindulgence that leads to obesity.
Fats have unfortunately obtained a social stigma; however, in the correct amount, lipids are
actually beneficial to an individual‘s health. Monounsaturated fats, such as canola and olive oil, and
polyunsaturated fats, such as omega-3, have great health benefits. They can reduce the risk of developing
atherosclerosis, heart disease, and inflammation. However, trans fat does in fact cause complications if
consumed too frequently.
In moderation, sodium is a vital part of a good diet. The human heart cannot function without it,
and yet, too much will increase blood pressure (Oz, 2011). An increasing problem with salty foods is that
the sodium (Na) binds to certain elements found in processed foodand causes a reaction that leads to a
stimulated appetite, meaning individuals consume more than what is necessary.
Ingesting antioxidants can help increase human health because it can result in rejuvenated skin and
lower dementia and resistance to Parkinson‘s disease and Type 2 diabetes (Oz, 2011). Good sources of
food to induce this prevention are dark chocolate, wine, and coffee.
Nutrigenomics have been linked to how the individual processes food. Certain aspects of the DNA
and the genes present in some people change how food is digested and how it affects the body. Another
important factor to staying healthy is exercise. Dr. Oz claims that there should be a balance between diet
and exercise; in fact, calories consumed must equal calories burned to maintain a perfectly healthy body.
If that scale is tipped so that there is an unequal balance, then the result will either be weight loss or
weight gain. Because the human brain is always looking for nutrients, not calories, eating a moderate
amount from every food group is essential. It is vital to eat in moderation, to ingest a certain amount of
fruits and vegetables, and to exercise (Oz, 2011).
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Nutrition
The most current food pyramid gives a detailed
account of what foods should be consumed.
The body uses nutrients for growth, maintenance, and energy (Wilson, 2007). Carbohydrates
yield the energy that the body requires. Sucrose and glucose are simple carbohydrates, while fiber and
starches are complex ones. Foods such as whole wheat bread, pasta, and rice contain primarily
carbohydrates. Unfortunately, it is easy to overindulge in these foods, but an effective way to avoid this
unhealthy habit is to eat until satisfied, not full.
Another key nutrient is protein because it stimulates growth, repairs cells, and maintains tissue.
These are extremely important for athletes who often induce stress on the bones and muscles. The
proteins are broken down into amino acids and peptides. Because they are so important for the function of
the body, protein levels can become dangerously low if there is an inadequate intake of carbohydrates or
fats. The body often uses protein as a substitute for missing nutrients to produce energy, but a low level of
any nutrient will lead to weakness and disease (Wilson, 2007).
Lipids, another source of energy, help maintain body temperature and are required for tissue
growth and hormone production. Too much of this group will lead to weight gain, as with any other
nutrient. In moderation, everything allows the body to function properly.
Vitamins help the immune system fight infection and regulate bodily functions. Minerals are
similar to vitamins because they aid the daily functions of the body. Water dissolves and carries nutrients;
it is not enough to consume nutrients alone because water is needed for transportation to every part of the
body. When all nutrients are present, their functions weave together in a seamless harmony.
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Economic Uncertainty
It is simply not enough to have a beneficial meal plan if one does not have the means to purchase
the food. Of course those with money have a clear advantage over the lower classes. In general, people
can afford what is required.
Food availability and resulting levels of consumption have increased throughout the years. The
food supply showed that the average American was consuming 3,800 calories per day in 2000; the highest
rate so far (USDA, 2001). The increase in calories directly means that there was a weight gain among the
people. Over 62 percent of the population was considered to be overweight; an increase of 46 percent
since 1980. These shocking statistics are a result of supply and demand, the availability of food. Other
than the calorie intake, another cause of weight gain is lack of exercise
Increase in calories andfood intake between 1983 and 2000.
Food expenditures have risen in 2001 to $844.1 billion, a 3.8% increase then the 2001 counterpart
(USDA, 2001). This rise was a result of a 5.5% income expansion from 2000. The cost of processing,
transporting, and distribution from American farms rose to $121 billion. This only represents 20% of the
total food expenses (USDA, 2001).
What a dollar spent for foodin 2000.
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Even given the strict diets followed by many consumers, America is on the path to having the
most obese population. The access Americans have to a sustainable food supply should result in a healthy
population. Yet, the opposite is true. Other countries in the world have people that struggle to survive on
what little food they can get. Diseases and malnutrition have spread around the globe due to a lacking
food supply in other countries.
The main problem with access is the need to spend immense amounts of money. Currently here is
national debt, and promoting a healthy diet is often ignored. The FDA is in charge of doing everything
food and drug oriented. Dr. McClellan, a business man and doctor of economics, introduced the idea of
efficient risk management where the FDA would only do things that have the most impact on society,
because it cannot complete every single task available (―Business: Food, drugs and economics; face
value‖ 2003). Challenges include how to inspect imports and medicine. These have to be completed, but
everything has a cost. The amount of money the FDA can spend is limited. After the most important task
has been accounted for, the nutritional problem can be assessed. Focusing on one aspect at a time will
yield better results.
Disease-Preventing Diets
Nutrition is a vital component of a healthy lifestyle, and many people forget how important it
actually is. An unhealthy diet can lower a person‘s life expectancy by decades, while a healthy diet can
extend a person‘s life above the average life expectancy. This in mind, it is crucial that people recognize
the nutrients that they are consuming and maintain a diet that will benefit their bodies.
Low-Carbohydrate Diets
People who have a low intake of carbohydrates are usually slimmer and have less fat. Some foods
containing this nutrient that are usually avoided and maintain body weight are white potatoes, rice, pasta,
and bread. Foods that are high in carbohydrates compel blood sugar levels to rise and, in result, insulin
levels as well. Eating foods that are composed of mainly carbohydrates leads to increased hunger levels,
and the best low-carb diets comprise a variety of whole foods. Although, crushed or refined fruits, beans,
vegetables, or whole grains are healthier than most foods, they have higher Glycemic Load (GL) levels.
Whole foods, such as All-Bran and Cornflakes have low GL‘s. A low-carb diet should also include foods
with healthy fats and protein (University of Maryland Medical Center, 2007)
Besides reducing fat in the body, a diet low in carbohydrates can improve sleep disorders and the
function of blood vessels. People who suffer from sleep apnea can benefit from this type of diet. Sleep
apnea is a disorder that is a result of abnormal pauses in breathing or swallowing while sleeping, and it is
a leading cause in daytime fatigue This disorder is more common in people who are overweight and
several researchers, from the Karolinska Institute, ran experiments which proved that low-carb diets have
a positive effect on sleep apnea (―Diet and sleep apnea‖, 2011.). In a similar way, a diet that is low in
carbohydrates improves blood vessel function by reducing fat, according to a study completed by Johns
Hopkins researchers. Loss of stomach fat allowed arteries to expand and helped the blood flow more
freely. Several overweight participants helped the researchers refine their idea that low-carb diets that
helped burn fat improved the overall health of the patient‘s vascular systems (―Improve blood vessel
function‖,2012).
Heart-Healthy Diets
Not only are fish tasty, but they are also important in lowering cholesterol levels. Oily fish such as
salmon, sardines, tuna, mackerel, and trout have omega-3 fatty acids that are very beneficial, unlike
saturated fats. Because of remarkable evidence from several studies on the subject, The Foodand Drug
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Administration announced that Omega-3 fatty acids lower triglycerides and slow down plaque growth in
the bloodstream, as well as reduce inflammation. Although fish are relatively high in calories, eating
reasonable amounts will benefit the health. A four-ounce serving of salmon provides 83% of the omega-3
acids a person needs a day (Griffin, 2005a).
A diet with oatmeal and oat bran also benefits the heart. These two foods contain soluble fiber,
which brings down low-density lipoprotein (LDL) cholesterol levels without reducing high-density
lipoprotein (HDL). The fiber helps absorb cholesterol in the intestines and releases it as waste instead
placing it into the arteries. Research published in 2005 the American Journal of Clinical Nutrition
suggests that a diet with oatmeal lowered cholesterol levels almost as much as cholesterol drugs.
Approximately five to ten grams of soluble fiber added to a person‘s diet can increase the strength of his
or her heart (Griffin, 2005b)
Diets containing soy and tofu also assist the heart by lowering blood pressure levels. An
important compound that lowers blood pressure, isoflavone, is present in soymilk, tofu, green tea, and
peanuts. Isoflavones increase the production of enzymes, nitric oxide (NO) that dilates the blood vessels.
The increased amount of NO reduces pressure from blood against the vessel walls. A medical student at
Columbia University, Safiya Richardson, completed research that suggests systolic blood pressure levels
in people with pre-hypertension could decrease as much as 10 mmHg with a diet of soy protein and other
healthy foods. This type of diet could reduce their chances of advancing to hypertension (―Soy reduces
blood pressure‖, 2012).
Components of a diet that strengthen the heart.
Fruits and Vegetables
Although it is important to keep a balanced diet containing each component of nutrition, eating
fruits and vegetables seems to provide the most superior benefits. Consuming an adequate amount of
these foods can prevent certain diseases, according to the United States Department of Health and Human
Services‘ Healthy People 2010 objectives. Fruits and vegetables fill important dietary needs and provide
protection against chronic diseases such as hypertension, certain cancers, and Type Two Diabetes (―Eat
your fruits and vegetables‖, 2011). Research completed by Paolo Boffetta and his colleagues suggests that
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eating proper amounts of these foods can slightly reduce the overall risk of cancer. Boffetta showed that
there was a small inverse between eating many fruits and vegetables and reduced cancer risk, and several
other studies supported this discovery. While vegetables and fruits may have some ability to prevent
cancer, other unhealthy lifestyle choices, such as smoking, can nullify the benefits that a healthy diet
provides (―Cancer protective effects‖, 2010).
Unhealthy Diets
Certain diets can improve health, while other diets cause negative effects. Some factors that cause
disease are out of a person‘s control, such as genetics, but eating well can provide your body with the
proper nutrients to prevent diseases. A diet low in nutrients is not able to protect the body against viruses
that lead to chronic diseases such as the common cold or the influenza. An unhealthy diet is a large factor
in obesity, disease, and decreased life expectancy (McLaughlin, 2011).
Negative Effects of Red Meat
A diet composed of red meat can have lasting negative effects. According to Nicholas Bakalar in
the New York Times, there is a link between red meat and mortality. Research conducted on 121,342 men
and women yielded interesting results; 5,910 people in the group died of cardiovascular disease and 9,464
people died from cancer. Accounting for the people who lived sedentary or dangerous lifestyle, the
researchers still found that a daily increase of three ounces of red meat was connected to a 12 percent
greater risk of dying, a 16 percent increased risk of cardiovascular death, and a 10 percent greater risk of
cancer-related death. Scientists deduced that if the patients had lowered their red meat consumption by a
half, mortality rates would have decreased 9.3 percent in men and 7.6 percent in women. These results
strongly suggest that consuming red meat is not only unhealthy, but can be deadly (Bakalar, 2012).
Another peril of having a diet with too much red meat is that it can increase chances of contracting gout, a
severely painful type of arthritis that causes joint inflammation. Frank Bruni, who is a meat-lover and a
frequent diner, once had a diet that included a surplus of red meat and alcohol. After being diagnosed with
gout, he had to quit eating most red meat and organ meat to avoid the excruciating burning and stabbing
feelings caused by the disease (Bruni, 2012).
White Rice
Research at the Harvard School of Public Health was conducted to determine the connection
between intakes of white rice and Type Two Diabetes. White rice is consumed worldwide and has a high
glycemic index (GI). Increased GI diets are known to heighten chances of becoming diabetic. The
participants of the study were taken from Asian countries, whose population consumes up to 4 servings of
white rice per day, and Western countries whose population eats much smaller amounts of white rice.
None of the participants were diabetic at the beginning of each study. With each additional serving of
rice, the study conducted separately on Asian and Western countries revealed that there is a 10 percent
higher risk of developing Type Two Diabetes. This research suggests that people in certain Asian
countries who eat a large amount of rice will have a higher risk of this type of diabetes (―Diabetes and
white rice‖, 2012).
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An example of nutritional information
printed on a box containing white rice.
Soft Drinks
Certain beverages also have the ability to affect a person‘s health in a detrimental way. Research
on soft drinks suggests that drinking too much can lead to vascular diseases or gout. Hannah Gardener
and her colleagues discovered that diet soft drinks were less healthy than regular ones. Her group studied
2,564 participants by inquiring how many soft drinks, diet and regular, that the people consumed and the
number of vascular problems that they had over a ten year time period. The study yielded surprising
information: people who drank diet soft drinks every day were 43 percent more likely to have a vascular
problem than people who drank none or people who chose regular soft drinks (―Soft drinks and vascular
disease‖, 2012). Research on regular soft drinks that are high in fructose suggests that frequent
consumption leads to an increased risk of gout in men. A study published in the British Medical Journal
investigates men 40 years or older with no previous history of gout. They were assessed on the amount of
regular soft drinks, diet soft drinks, and other fruit drinks high in fructose that they consumed over 12
years. Other health factors were analyzed and after the 12 year period the researchers found that, in the
group of men, 755 cases of gout arose. Among the men, there was an 85 percent increased risk of gout in
men who consumed five to six servings of soda per week. Both of these studies display the effects of
consuming any type of soft drink or drink high in fructose; the results are not desirable (―Sugary soft
drinks and gout‖, 2008).
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Soft drinks are a hazard to good health.
Effect of Diet on Epigenetic Expression
In addition to affecting a person‘s own health, certain nutrition habits have the ability to influence
future generations. Environmental factors, such as diet, are able to alter DNA through epigenetic
markings. These marks reform the ways in which genes are expressed without changing the DNA
sequence permanently by adding or subtracting methyl groups. S-Adenosyl methionine, folic acid, and B
vitamins are well-known nutrients that enter metabolic pathways, and when these nutrients are regularly
consumed, gene expression can easily be altered. The foods that people include in their diets have the
capability to affect their epigenetic expressions either negatively or positively, andin response, these
altered genes are passed on to the offspring (―Nutrition and the epigenome‖, 1969).
Chemicals and additives also have the ability to affect epigenetic marks. Bisphenol A (BPA),
which is a compound in the polycarbonate plastic used in water bottles, causes negative health effects in
offspring. Epigenetic research showed that when pregnant yellow mice were given BPA, some of the
mice gave birth to yellow, unhealthy mice. When the yellow mice that were fed BPA were given a diet
rich in methyl foods, the majority of their offspring were healthy and brown; they seemed to counter the
detrimental effects of the BPA exposure (―Nutrition and the epigenome‖, 1969).
A woman‘s nutrition during pregnancy has a large impact on her children, but a man can also
influence his offspring‘s health. Research by a preventive-health specialist, Dr. Bygren, aimed to discover
how the switch in the amount of food available affected the offspring of that particular generation in both
men and women. This research yielded intriguing information. The results revealed that boys who
switched from famine to feasting in a single season later fathered children and grandchildren whose life
spans were decreased from those who had not overeaten. Further research suggested that changing
nutrition also affected women‘s offspring in the same way (Cloud, 2012).
Knowledge of epigenetics has given scientists many new ideas on how to prevent and treat
diseases and genetic disorders. A study published in the journal Clinical Epigenetics suggests that
vegetables are made up of compounds that might have the ability to prevent and protect people from
diseases such as cancer. The scientists leading the investigation say that this so-called epigenetic diet
includes cauliflower, broccoli, cabbage, soybeans, kale, green tea, fava beans, thenspice turmeric, and
grapes. When mothers tell children to eat their vegetables, they‘re protecting them from fatal diseases.
The compounds in the vegetables that make up an epigenetic diet suppress gene abnormalities that cause
horrible diseases such as cancer and Alzheimer‘s (Blanchard, 2012).
[...]... supplements Multivitamin and multimineral use was the most frequently reported and between 28 and 30% of the surveyed population reported using dietary supplements containing vitamins B-6, B-12, C, A, and E; 18–19% reported using iron, selenium, and chromium; and 26–27% reported using zinc- and magnesium-containing supplements (Bailey et al., 2011) Although the safety of dietary supplements is in question,... keeping infants indoors), increased skin pigmentation, reduced in- utero exposure, and reduced capacity to synthesize vitamin D with increasing age.‖ Those with dark skin, pregnant or nursing women, those living in mild climates, the elderly, and those with conditions such as celiac disease are particularly at risk (Saunders et al 2011) Rickets is caused by poor diet and lack of fresh air and sunshine... method for preventing pre-eclampsia, thought to be caused by a deficiency of L-arginine, an amino acid essential in blood circulation The study consisted of three groups of pregnant women The first group was given food bars containing L-arginine and antioxidant vitamins (Vitamin A, C, and E are all antioxidants) The second group was given bars containing just the vitamin supplements and the third group... difficulty performing its normal functions Organs such as the pancreas and intestines suffer, and often processes such as the pancreatic exocrine function or the intestinal permeability begin to break down Enzymes used to digest consumed food are less abundant, and this can even result in secondary lactose intolerance on certain occasions In addition, diarrhea is a leading cause in loss of water and electrolytes,... bb2c799464af190e07f.jpghttp://www.usda.gov/factbook/chapter2.pdf 18 Chapter 2 Vitamins and Minerals Barry Biletch, John deRivera, and Aniket Lachyankar Introduction Organic molecules that are required in small amounts by organisms are called vitamins, and they can be divided into two groups: water soluble and fat soluble Water soluble vitamins include the B vitamins and vitamin C These vitamins are flushed out of the body through urine on a daily basis As... livers of seals and polar bears, acute toxicity occurred because of the massive amounts of vitamin A that they were ingesting (Vitamin A, 2007) Not all vitamins need to be ingested in their final form because the body can synthesize some vitamins from other molecules Vitamin A is produced from beta-carotene and other carotenoids (Vitamin A, 2007), vitamin D is synthesized in the skin when in direct contact... getting a daily dose of vitamins easier David Edwards, a biomedical engineer at Harvard University, has invented a product he calls ―Le Whif.‖ The liver and intestinal tract can damage vitamins and are also slow to absorb the vitamins into the bloodstream To combat this, Le Whif grinds vitamins into aerosol particles that can be packaged into spray cans and then inhaled Inhalation provides a more direct... exclude fruits and vegetables The symptom is also known as scurvy and results in stunted collagen synthesis Ecchymoses, petechiae, bleeding gums, hyperkeratosis, and difficulty in healing wounds may occur as well as fatigue, malaise, pain in the joints, edema, anxiety, and neuropathy Thiamine (vitamin B1) assists in energy metabolism and assembling tissues Deficiency occurs from lack of intake (such... This mainly affects infants and toddlers, but women of childbearing age are also at risk Iron deficiency anemia occurs from a lack of dietary iron The lack of ingestion of meat or frequent ingestion of tannins or phytates causes internal problems that results in intestinal parasites, hemoglobinopathies, and chronic infections Lack of iron can lead to stunted psychomotor abilities in infants and cognitive... example, a large intake of vitamin A in the diet and supplements will prevent blindness With old age you do not metabolize vitamins and minerals and therefore you should take more Food supplements delay ageing Food supplements prevent cancer Food supplements are safer and healthier than prescribed medication Food supplements replace the deficiencies caused by a poor diet Food supplements . 1 Got Food? Recent Advances in Food Science and Technology ~~~~~~~~~~~~ An e-book co-authored by the Class of 2013 Massachusetts Academy of Math and Science ~~~~~~~~~~~~. clothing, moving to temperate climates, and the tradition of keeping infants indoors), increased skin pigmentation, reduced in- utero exposure, and reduced capacity to synthesize vitamin D with increasing. beta-carotene and other carotenoids (Vitamin A, 2007), vitamin D is synthesized in the skin when in direct contact with UVB radiation (Vitamin D, 2007), and vitamin K is made by bacteria living in the intestines