Be vitamins?

We all hear people talk about vitamins. The B vitamins, in particular, seem to be coming up more often. So what is a vitamin, and specifically what are B vitamins?

A simple definition of a vitamin is a small molecule that the body needs to carry out certain reaction(s). In our bodies, there are an unbelievable number of chemical reactions happening every second, and, though only effecting a small portion of those reactions, vitamins are crucial to our health and survival.

So where did the letters and numbers for vitamins come from? Essentially the vitamin names came from the order in which they were discovered and whether or not they were water soluble (i.e. can be dissolved in water). But more on that in a future post...

Here is a brief overview of the B vitamins as well as links for more information.

Vitamin B1
B1, or thiamine, is most notable for its role as a cofactor in the production of energy, in the form of adenosine triphosphate (ATP), in our bodies.

Vitamin B2
B2, or riboflavin, is important in reduction and oxidation reactions, or redox (pronounced like "re-docks") reactions. Essentially, these reactions allow for transfer of electrons.

Vitamin B3
B3, or niacin, like vitamin B2, is also important in redox reactions. Niacin can also decrease lipid (fat) levels in the blood.

Vitamin B5
B5, or pentothenate, is needed for energy production and for the production of fatty acids.

Vitamin B6
B6, or pyridoxine, is a cofactor in a number of very important reactions. Vitamin B6 helps in the production of vitamin B3, in the production of properly functioning red blood cells (via its role in heme synthesis), and in the production of important neurotransmitters such as dopamine, just to name a few.

Vitamin B7
B7, or biotin, is involved in the production of fatty acids and glucose in our bodies, among other roles.

Vitamin B9
B9, or folate, is important in DNA and RNA production.

Vitamin B12
B12, or cobalamin, is important in DNA and RNA production, metabolism, and maintenance of the central nervous system (including the brain and spinal cord).

Are people naturally overweight?

I hear that some people are naturally overweight. Is there any truth to that?

In short, yes. There is some evidence that there are a number of genetic (and possibly even viral) associations with obesity.

 

However, environment plays a big role. Unfortunately, this is not something one can always control. If an individual is raised by overweight individual(s), he or she will likely share the same diet. So if someone is raised on fatty, unhealthy food and/or too much food, they may be overweight as a child. And that weight can be tough to lose later in life. In addition, TV, video games, and a sedentary lifestyle are making this worse, as kids used to exercise much more frequently.

Some individuals are more likely to be overweight, just as some individuals are more likely to have a heart attack, have cancer, or have other health issues. However, as with many predispositions for health issues, a good diet, exercise, and a healthy lifestyle can greatly reduce the risk. Many individuals who have, based on their genes, an increased likelihood for being obese maintain a normal weight through a healthy diet and exercise. 

To read more: http://www.cdc.gov/features/obesity/

The folate story

Folate (aka folic acid or vitamin B9) is a vitamin crucial for a number of processes related to DNA production/repair and cell division/growth. Folate is naturally found in fruits, vegetables, and beans.

A number of years ago, researchers recognized that a lack of folate in pregnant mothers could contribute to defects of the spine and/or brain of their newborns (called neural tube defects). As a result, beginning in 1998 folic acid fortification of grain and cereal products became mandatory in the U.S. In addition, women who are pregnant or planning to become pregnant often should receive folate supplementation to ensure adequate levels.

 
Most individuals receive enough folate in their diet. However, for women of childbearing age, individuals who consume large amounts of alcohol, and for individuals with celiac disease or other malabsorptive gastrointestinal disorders, it is important to ensure adequate levels of folate.

To read more: http://www.health.harvard.edu/newsweek/the-ups-and-downs-of-folic-acid-fortification.htm

Calories and metabolism

Ever wondered what a calorie is? How the values on nutrition labels are calculated? Why two people who eat the same amount of food may gain weight differently? This video addresses a few of these questions:

How does weight loss surgery work?

There are a number of different weight loss procedures with different goals. Here are a few:

• Gastric banding
• In this procedure, a band is placed around the top of the stomach. The tightness of this band can be adjusted via adding or removing saline to the access port. Essentially, the goal is to stimulate a feeling of fullness. A very notable advantage of this procedure is that it is reversible.

• Gastric bypass
• In this procedure, a surgeon reroutes the way that food passes into the digestive tract. Gastric refers to the stomach, so as described by the name, this surgery causes food to bypass the stomach (and the initial part of the small intestine). As digestion normally occurs in these bypassed areas, enzyme supplementation is sometimes necessary to make sure nutrients can be properly absorbed.

 

• Sleeve gastrectomy
• In this procedure, a surgeon removes part of the stomach. The rest of the digestive system is left otherwise intact.

All of the procedures are associated with side effects, sometimes severe, and in some cases the procedures do not work or lose their effectiveness over time. To read more: http://win.niddk.nih.gov/publications/gastric.htm

Some lesser known sources of potassium

For many, the first food that comes to mind when you think potassium? Banana.

Bananas are great sources of potassium, but there are a number of sources of potassium than many may not be aware of. For example, a sweet potato, a potato, and certain types of fish all have more potassium than a banana. In addition, spinach, milk, and orange juice are all great sources of potassium. 

For a full list of potassium-rich foods, visit: http://www.health.gov/dietaryguidelines/dga2005/document/html/appendixb.htm. 

Why is too much salt bad for us?

Salt, or sodium chloride, is essential for humans to survive. But why? And why is too much a bad thing?

• Is salt good for us?
• Absolutely. Here's why:
• Salt is very important in things like muscle contraction (including keeping your heart beating), nerve conduction (e.g. when you accidentally touch a hot stove, you feel pain and perhaps shame depending on how often said incident occurs—both are controlled by nerve impulses), and, among many other functions, in keeping the cells in our body alive.
• Nerdy aside: Salt plays a crucial role in maintaining the electrical gradient of our cells. Essentially, the cells in our bodies have a slight electrical charge. Among many other receptors, there is one (called the sodium potassium ATPase) that pushes sodium out of cells in exchange for bringing potassium into cells. Both sodium and potassium are positively charged, but the receptor pushes out more sodium than it brings in potassium, leading to a negative electrical charge within our cells.
• We need water. But without salt, our bodies would not be able to properly utilize water. Water has a property known as osmosis. Essentially, osmosis is the ability to travel from one compartment to another (e.g. from outside of a cell to inside of a cell) without using energy. Within our body, the most important regulator of this process is typically salt. So an absence of salt leads to water not being able to properly enter tissues, cells, and other parts of our bodies where it is needed.

• Then what’s the problem?
• We need some salt. If you look at the recommended daily intake on the back of food products, sodium will always be there as something that we should be consuming. The problem is that we sometimes eat way too much, especially when eating certain types of foods. 
  

• Salt alters the flavor to food (taste receptors on the tongue respond directly, among other things, to sodium). In addition, salt can help preserve foods because too much salt can be dangerous/deadly even to bacteria. As a result of our affinity for salty foods and its ability to increase the shelf-life of food, salt has made its way as a staple into our diet.
• History aside:
• Before the days of canned foods and McDonalds, some individuals used to salt or smoke meat to keep it from spoiling.
• Goiter and other thyroid conditions can result from a lack of dietary iodine. Beginning in 1924, iodized salt was introduced to the U.S. market. Most salt in the U.S. is now iodized, meaning it contains iodine, greatly reducing the incidence of goiter
• Americans typically eat too much salt. To understand part of why this is a bad thing, we’ll need to talk about the concept of osmosis brought up earlier. 
• Say you have a single cell floating in a blood vessel. If you then add a bunch of salt into the blood vessel, but not the cell, water will immediately flow outside of the cell. Once it loses water, there is less volume in the cell, so it will shrink. As I’m sure you can imagine, our cells aren’t too crazy about that, so our kidneys hold on to more water in order to get our cell back up to normal size. But in order to do this, additional water has to be added to blood vessels too. So the end result is that our cells stay a normal size, and our blood vessels have more water in them. This increases the pressure inside our blood vessels. When the body cannot adjust appropriately, this results in hypertension.
• Hypertension isn’t a good thing. It’s generally defined as a blood pressure higher than 140/90. Hypertension increases the likelihood of heart attack, stroke, and all sorts of bad things.
• How does hypertension contribute to those?
• Hypertension implies a high-pressure system in your blood vessels. Much like a pressure washer can do more damage than a hose with a weak stream, higher pressure can damage the walls of our blood vessels. Damaged vessel walls enable things that have no business in our blood vessels to enter into the walls, leading to inflammation, atherosclerosis (essentially hardening and narrowing of arteries), and other negative effects.

• So, in short, too much salt over a long period of time can increase the risk of developing hypertension. Hypertension is a bad thing.