Unbalanced diet

Biology Blog Post
Huang Liushu (9) 3SE

Everyone could agree that they eat some foods more frequently than others. This causes the "unbalanced diet trend", experienced by more than half of the population around the world. Here are some bad effects of consume too much carbohydrates and fats, including water retention, arteriosclerosis(clogged arteries) and coronary heart disease.

Carbohydrate
As we know, there are two types of carbohydrates: monosaccharide(simple carbohydrates) and polysaccharide (complex carbohydrates). Simple carbohydrates like glucose, galactose and fructose can only provide temporary energy that plunges down once used by the body.
Complex carbohydrates, on the other hand, provide more long-term effects because they are the main energy storage products. Because of this effect, some people load up on carbohydrates in order to gain quick energy stores. This causes the concentration of carbohydrates to become higher. Hence more water is required for osmosis through the concentration gradient. This "carbohydrate loading" behavior leads to a bloated feeling and water retention and/or fat storage.

Fats
Here I need to mention one kind of fat which we need to pay more attention to -like substance found in all animal products, meats and eggs - called cholesterol. Cholesterol is used to build cell membranes and produce hormones, vitamin D, and other important enzymes in our bodies. Do you wonder whether it is good or not? In reality, too much cholesterol in the blood can lead to clogged arteries and heart disease.
There are two major types of cholesterol that circulate throughout the blood in protein packages: Low Density Lipoprotein (LDL) and High Density Lipoprotein(HDL). High levels of Low Density Lipoproteins can result in arteriosclerosis -clogged arteries- and coronary heart disease. High Density Lipoproteins are often recognized as the "good cholesterol" because they are responsible for the transport of excess cholesterol back to the liver for removal from the body. With the help of exercise, the levels of HDL in the blood will increase, thereby preventing clogged arteries and heart disease.
There are 3 types of fats: saturated, polyunsaturated and monounsaturated.
Saturated fats raise blood cholesterol and are identified by their solid state at room temperature. Some examples are butter, coconut oil, palm oil, and the fat in meats and whole milk dairy products.
Polyunsaturated fats have two main effects involving cholesterol. The good effect is to lower Low Density Lipoprotein blood cholesterol levels. However, the undesirable side effect caused by the excess polyunsaturated fats is also prominant- the protective High Density Lipoproteins (HDL) cholesterol is lowered at the same time. Polyunsaturated fats are liquid at room temperature and can be found in vegetable oils including corn, safflower, and soybean.
Altough monounsaturated fats also lower LDL levels in the blood and liquid at room temperature, they have not been found to negatively affect the HDL levels. These fats are found in foods such as olives, olive oil, canola oil, peanuts and peanut oil.
In general, excessive intake of fat, simple sugars and alcohol will cause a rise in triglycerides and storage of fat. Triglycerides are fats found in the blood and stored in body fat. Those fat stores are responsible for the formation of adipose tissue, more commonly recognized as those flabby, undesirable areas on the body.

In conclusion, we must control our consumption of carbohydrates and fats.

Information taken from http://health.rutgers.edu/brochures/pyramid.htm

composition of chocolate

Biology Blog Post
Huang Liushu (9)
3 Service

Chocolate, made from cacao seeds and usually sugar, is thought to be an effective food to provide energy, especially for athletes who require more energy than normal people.

Nowaday, cholocate is used as an ingredient to make jams, cakes, drinks, etc. This fact makes us more curious about its composition.

The composition of cocoa and chocolate has been extensively studied. The fat in chocolate, which is primarily derived from cocoa, is comprised of two saturated fatty acids, palmitic and stearic acids, and the monounsaturated oleic acid, in addition to a small amount (less than 5 percent) of other fatty acids.

Although consumption of saturated fats is considered to raise cholesterol, and thus raise the risk of heart disease. Nonetheless, regular consumption of cocoa butter and chocolate has been repeatedly shown to not raise blood cholesterol.

Further research has shown that this is probably due to the relatively high concentrations of stearic acid, which studies have shown to have a cholesterol-neutral effect, and oleic acid, which is known to have mild cholesterol-reducing effects. Therefore, the fats present in chocolate are not real threats as people thought before.

In addition to the fat and simple sugars present in chocolate, the cocoa component in chocolate is rich in a number of essential minerals, including magnesium, copper, potassium and manganese. Indeed, chocolate is thought to be one of the largest single contributors of copper to the diet in the United States. For more information on these nutrients, see BellyBytes.com: Essential Nutrients

Here is a table showing components of 100 g of good quality chocolate.



From the table, we can see that lipids and carbohydrates are abundant in chocolate. Chocolate also contains many types of mineral substances and vitamins. The content of each nutrient is varied a little in different types of chocolate.

Those values can of course be changed by the presence of additives e.g. wal-nuts, hazel-nuts, almonds, raisins and other dried or candied fruit. Chocolate in fact is a high-grade and natural food.

Some people suggest that we should not eat chocolate because it is sweet but not nutritive. However, compared to pure water (distilled water), which does not contain anything else except water, adequate consumption of chocolate is still acceptable. No matter how nutritious food is, we cannot consume too much. We still need to

overcome our desire and eat properly.

Information taken from http://www.fitnessandfreebies.com/fitness/chocolate.html
http://www.info-galaxy.com/Chocolate/From_Bean_to_Chocolate/Chocolate_Composition/chocolate_composition.html

Most Dietary Supplements Are Bad For Health

Biology Blog Post
Kong Eng Hong (14)
3 Service
14th April 2007

In the craze to look for a quick fix to lose weight, many dieters are often vulnerable to the many dietary supplements which often proclaim something along the lines of "100% Natural Herbs melt the pounds away, without any diet or exercise at all!", "Can burn up more 150% more calories than running 5 miles!" or "Eliminates fat content of 5 pizzas!". What most dieters do not realize is that most dietary supplements are hazardous to health, and most do not actually accomplish what they proclaim to do. Most dietary supplements are actually not safe for the body at all!

What are dietary supplements? Dietary supplements are products that include vitamins, minerals, amino acids, herbs, or botanicals (plants) - or any concentration, extract, or combination of these - as part of their ingredients. One can purchase dietary supplements in pill, gel capsule, liquid, or powder forms. Dietary supplements meant to aid in weight loss and atheletic performance. However, most dietary supplements defeat this purpose and perform the opposite instead.

Fortunately, most dietary supplements are checked and tested by local health authorities before they are allowed to be shipped and sold to Singapore, thus most dietary supplements sold in Singapore are safe to an extent. However, this does not mean that the dietary supplements available locally are totally safe; they must be taken in accordance to guidelines to be safe and beneficial.

The most common example of dietary supplements are diet pills, also known as slimming pills, used by many individuals to mantain and lose their weight. Most diet pills do not actually work, and even if they do, they work only when accompanied with a balanced diet and exercise. Diet pills are not needed for efficient and adequate weight loss; only exercise and a balanced diet is capable of achieving that. Diet pills can be addictive and can also have harmful side effects even when they are taken according to the doctor's directions. Diet pills also have many harmful health effects which include anxiety or nervousness, irritability, insomnia and a feeling of restlessness or hyperactivity, high blood pressure, tightness in the chest, heart palpitations, a heart attack, stroke or congestive heart failure, digestive tract problems like vomiting, diarrhea, constipation or other stomach pains, fevers, a dry mouth, headaches, dizziness, blurred vision, profuse sweating, hair loss, menstrual cycle and sex drive disturbances and urinary tract problems. In the case of overdose, users can experience tremors or convulsions, confusion or hallucinations, breathing problems, renal failure or heart attack.

Therefore, it can be seen that diet pills need to be taken with caution due to all of the physical risks; it may be even better not to use diet pills at all! But there are emotional risks involving the usage of diet pills too. Often those trying to lose weight may start to feel emotionally dependent on the pills. They may attribute their initial success to diet pills only, forgetting any diet modifications, exercise or other lifestyle changes that may have been the true reason for the weight loss. People will often 'pill hop', trying one new pill after the other, looking for the magic cure that will let them continue to eat whatever they want but still lose weight. However, only a balanced, sensible diet combined with exercise has been proven to keep weight off over any amount of time. And no pill will cause the lifestyle and emotional changes needed to stop overeating and start losing weight.

Therefore, it can be concluded that many dietary supplements are harmful for health, causing many side effects, and that for genuine weight loss, it is best that dietary supplements not be used at all; one should only rely on adequate exercise and a balance diet to lose weight.

Information taken from:
http://www.kidshealth.org/teen/food_fitness/dieting/diet_supplements.html
http://www.slimming-diet-pills.info/

Irony: Dieting may actually be harmful to health

Biology Blog Post
Kong Eng Hong (14)
3 Service
14th April 2007

Usually, obese individuals go on various diets in the ambition to lose weight, most with the typical reasons of looking better, feeling better and most importantly, being healthier, as obesity has been known to cause many health problems and heighten the chances of getting certain sicknesses and diseases; such as an increased risk of potentially fatal health problems such as heart attacks, high blood pressure and diabetes. However, several studies have shown that many misguided dieting methods are actually harmful to health; which is highly ironic, taking that most go on diets to improve their own health.

An example of a harmful dieting effect is known as the "yo-yo effect", in which an individual constantly loses weight and puts them back on. Doctors say that repeated change in body weight eventually puts additional stress on the heat and leads to other health problems; in which dieters put themselves in the risk of a heart attack. Among the potential ailments stemming from repeated weight loss and regain are cardiovascular disease, stroke, diabetes and altered immune function. Further more, the dieters who lose the weight initially are found not only to gave gained back the pounds and kilograms, but have ironically been shown to gain more, defeating the purpose of a diet.

Researchers have concluded that for many individuals, it would have been healthier for them not to have tried to lose weight by dieting at all. Exercise, on the other hand, appears to have been more helpful. Researchers identified exercise as a key researcher leading to sustained weight loss. Studies consistently find that dieters who exercised the most also had the most weight loss.

The "yo yo effect" is caused by "yo yo dieting", a diet, or rather, diets in which obese individuals resort to highly extreme ways to lose weight, often with the typical and highly upsetting and discouraging result: initial loss of weight, then regaining of the initial weight loss and even more weight later on. This is as many dieters look for quick fixes to their weight problems, either by starving themselves or by going on fad diets. However, as soon as they revert to their unhealthy eating habits, the weight is regained in full force; bringing along with it many health risks and problems which may be potentially fatal.

Therefore, it can be seen that the typical yet highly successful dieting method of adequate exercise and a healthy diet is the best way to shed the pounds and kilograms; quick fixes and fad diets are not the way to go.

Information taken from:
http://www.ahealthyme.com/topic/yoyodieting

What is harmful dieting? There are two forms of this, the first is when people cut down on all kinds of food, besides those that are 'confirmed' unable to contribute to any weight gain. By these I mean, fruits and vegetables. Dieting is harmful when the person is dieting without a doctor's advice or when he or she is not clear what her body truly needs, and is merely dieting according to her 'whims and fancies'. The second form is eating in large servings the food that the body doesn't need. This leads us to an important question: What are the effects of harmful dieting, really? This post of mine shall serve to inform all 'diet-ers' out there to prevent them from making a wrong choice.

I will start by discussing the effects of the first form of harmful dieting: eating too little and probably none of the food contaning nutrients that the body needs.

In general, these diets usuallly lead to low energy levels and increased fatigue. These are the mild effects. First, a low-carboyhydrate diet. People have to be careful about this because, according to the information found in this website (link below), such diets encourage fats to be stored, and thus add to weight gain, too. This can be a potential cause for atherosclerosis (heart and blood vessel disease). For women (please refer to link below), harmful effects include menstrual dysfunction or amenorrhoea (absence of periods), which in turn may cause bone eating, and osteoporosis.

http://www.bbc.co.uk/health/healthy_living/fitness/energy_disordered.shtml

Second, high-protein diets can cause kidney damage due to the lack of fibre in the diet, and the constipation may be unbearable. Low fibre, high fat can cause bowel cancer, as well. So, do have plenty of carrots and apples.

(Click to enlarge)

This diagram illustrates the effect I discussed about earlier, on insulin.

www.medscape.com

http://www.bbc.co.uk/health/ask_the_doctor/dietslowcarb.shtml

What are the solutions?

All in all, I would like to say that it is MIND OVER MATTER. Choose the right foods, exercise regularly. Persevere, be determined. No solution is absolute rubbish.

Ong Hui Yu 26/3 Service

Chocolate!

Biology Blog Post
Kong Eng Hong (14)
3 Service
27th March 2007

Chocolate is, to many, one of the most heavenly treats known to man. The reputation of Chocolate has been negative in the past, with decayed teeth and failed diets blamed on Chocolate. However, upon recent research, the many negative myths and beliefs about Chocolate have been dispelled, with the many health benefits of Chocolate being gradually uncovered, much to the delight of the any Chocolate lovers out there.

The Benefits of Chocolate:
* Cacao, the source of chocolate, contains antibacterial agents that fight tooth decay. Of course, this is counteracted by the high sugar content of milk chocolate. So, it can be seen that Chocolate is not all to blame for decayed teeth!
* The smell of chocolate may increase theta brain waves, resulting in relaxation.
* Drinking a cup of hot chocolate before meals may actually diminish appetite.
* Men who eat chocolate live a year longer than those who don't.
* The flavanoids in chocolate may help keep blood vessels elastic.
* Chocolate increases antioxidant levels in the blood.
* Mexican healers use chocolate to treat bronchitis and insect bites.
* The carbohydrates in chocolate raise serotonin levels in the brain, resulting in a sense of well-being.

What Chocolate Won't Do:
There are many myths and half-truths about the effects of chocolate on the human body. Here are the latest findings on several of them.
* Studies show that chocolate is not a causative factor in acne.
* Chocolate is not addictive.
* Chocolate contains stearic acid, a neutral fat which doesn't raise bad cholesterol.

But On The Negative Side...
1. Chocolate may trigger headaches in migraine sufferers.
2. Milk chocolate is high in calories, saturated fat and sugar.

Therefore, it can be sent that Chocolate is not all that bad, but not entirely wondrous either. Like any other foods, Chocolate is to be eaten in moderation.
Information taken from http://www.momscape.com/articles/chocolate.htm

Post: Dieting and its Effects

Biology Blog Post
Kong Eng Hong (14)
3 Service
27th March 2007

Nowadays, bombarded with the media’s negative messages and bad celebrity influences, people around the world, self conscious teenagers in particular, are pressurized to diet and lose weight rapidly by using extreme methods which often do not work and have severe consequences. Many weight obsessed teenagers often resort to unhealthy dieting methods instead of losing weight safely. They were most likely to skip meals, use diet pills or laxatives, smoke, binge and vomit to lose weight. What these teenagers do not take into consideration are the many harmful effects of dieting on their bodies.

Many teenagers nowadays suffer from eating disorders such as anorexia and bulimia, in which these eating disorders are not only physical but psychological. Anorexia is an eating disorder where people usually starve themselves in a desperate attempt to lose weight; and Anorexia sufferers are often plagued with the illusion that they are very overweight and have an intense fear of becoming fat, despite the fact that most people suffering from anorexia are underweight or unhealthily thin. Bulimia is another psychological eating disorder. Bulimia is characterized by episodes of binge-eating followed by inappropriate methods of weight control (purging). Inappropriate methods of weight control include vomiting, fasting, enemas, excessive use of laxatives and diuretics, or compulsive exercising. These two eating disorders are highly rampant among teenagers today, where becoming thin is a huge priority to gain acceptance among one’s peers.

However, the harmful effects of these extreme ways of dieting are less known than the diets itself. Extreme dieting interferes with one’s metabolism and fools one’s body into thinking that it is going through a starvation cycle. If extreme dieting is continued, the body will learn to compensate for these starvation waves by evening the body metabolism out, and one would gain a lot more weight suddenly during the non-diet phase and lose less during the diet phase, in which this is a natural body reaction. The only sensible way to lose weight is to have a balanced, healthy diet; in which this is something most teenagers do not, unfortunately, realize.