Wednesday, October 20, 2010

Which Vitamin D to Buy?

First of all, supplements are available as Vitamin D2 (Ergocalciferol) or Vitamin D3 (Cholecalciferol). The 25-Hydroxy Vitamin D test determines the combined level of Vitamin D2 and D3. Skin of animals, including humans synthesize the D3 from the Ultra Violet B (UVB), while plants synthesize D2.
To read why we need Vitamin D, and what may cause deficiency even when you think you are getting enough sun, see my previous post here.

Vitamin D2 or D3?

For more than 70 years, D2 has been administered to children and adults to successfully increase Vitamin D level in the blood. In last few decades, some scientific studies suggested that D3 is more effective than D2 as our skin is anyway supposed to synthesize D3. However, more recent studies suggested that D2 can be as effective as D3.
I didn’t go to medical school, but my doctor didn’t have a clue either, so I had to do my own research. I haven’t come across any study or article that would suggest D2 is better than D3. Please point me to one if there is out any. Does that mean when possible take D3 instead of D2? I would like to think so.
Here is a compilation from an MD, Dr. Christensen on why D3 over D2 [Reference]:
  • UVB light from the sun strikes the skin, and humans synthesize vitamin D3, so it is the most "natural" form. Human beings do not make vitamin D2, and most healthy fish contain vitamin D3.
  • Vitamin D3 is the same price as vitamin D2.
  • Vitamin D3 may be less toxic than D2 because higher concentrations of D2 circulate in the blood when consumed (compared to vitamin D3). It does not bind as well to the receptors in the human tissues compared to vitamin D3.
  • Vitamin D3 is the more potent form of vitamin D, which is a potential benefit. For example, obesity tends to lower blood levels of vitamin D, so a more potent form is needed.
  • Vitamin D3 is more stable on the shelf compared to D2, and is more likely to remain active for a longer period of time and when exposed to different conditions (temperature, humidity, and storage). This is perhaps why the amount of vitamin D2 in certain fortified food products have been significantly lower than that advertised on the label in numerous instances.
  • Vitamin D3 has been the most utilized form of vitamin D in clinical trials, and there have only been a few clinical trials of vitamin D2 to prevent bone fractures in adults.
  • Vitamin D3 is more effective at raising and maintaining the vitamin D blood test (again, D2 binds less tightly to the vitamin D receptors in the body; therefore, D2 does not circulate as long in the body, which means it has a shorter half-life).

Choosing the Right Supplement

  • D2 and D3 are fat soluble and is best taken in a gel capsule form. So, stay away from tablets.
  • D3 supplements are derived from animal base, some of D2 are plant based. So, vegans may prefer the plant based D2
  • It appears that USA Food and Drug Agency (FDA) has not approved D3 yet. So, for high dose of Vitamin D, where prescription is required, you may only get D2. However, I found a few high dose D3 available without prescription too.
  • Go with a brand you trust. If you are new to the vitamin world, like me, I had to do some more research.

Selecting the Product to Buy

Based on the reviews I narrowed down to the following products:
  • HealthyOrigins - Got the best deal on Soap.com with free 2-day shipping and 15% discount code: ANXX6983. The shipment promptly came in the next day!
  • ProHealth Vitamin D3 Extreme™
  • Biotech Vitamin D3
  • Now Foods Vitamin has D-2 and D-3 products
  • Deva Vegan Vitamin D2

Taking the Capsule

    Check with your doctor, mine suggested to take after full meal, otherwise it can upset stomach.

Friday, October 15, 2010

Under Sun, but no Vitamin D!

Do you think you get enough Sun? You may have to think again! 

I sit in an office with huge windows facing the Sun all day long and my office is in the so called “sunny” California. I figured I was getting enough sun-light for my body to make Vitamin D. But, my recent blood test showed that I am grossly deficient. MayoClinic has a short, but good article on why our body needs Vitamin D. With this post I am hoping to increase the awareness of growing deficiency in VitD among people around the world.


Sun-light and Deficiency in VitD

Enough sunlight, then why the deficiency, you ask? There can be several reasons. I am not a medical professional, but the interesting ones I found in my research:
  • Office windows are usually tinted, which blocks all of UVB (required by skin to synthesize VitD) and blocks only some of UVA (can be very harmful and causes aging of skin - read the 911skin report)
  • Sunscreen, even SPF 8 blocks 95% UVB [Reference]
  • If you are not in a tropical country, during winters sun is at an angle, such that all or most of UVB cannot penetrate atmosphere. But, all the UVA may still make it’s way.
  • Other medical conditions


Proper use of Sunscreen

You have to use your own judgement on when and where to apply the sunscreen, but the general recommendations I found on internet forums that actually make sense:
  • Always protect your face
  • For rest of the exposed body parts, don’t apply sunscreen inside home. Go out in the sun and apply sunscreen after 15-20 mins. Darker skin or people with tan may need more time. Basically, apply sun screen once your skin feels warm, but before it gets the burn.
  • Always wear sunscreen near the sea beach, as white sand and water may reflect sun rays and UVA will burn skin faster than your skin can make VitD.

Are you Deficit in VitD?

Ask your doctor about the 25-Hydroxy Vitamin D blood serum test, and if possible get the VitD level tested during regular checkups, at least once a year. Preferred frequency of test seems to be once after summer, and once after winter. Check with your insurance if it will cover the test, some don't seem to cover the VitD test.

Sources and Supplements of VitD

There is very little Vitamin D in food sources and it may not be possible to get the daily value just from food sources. See the food chart for VitD provided by National Institute of Health, Office of Dietary Supplements. 

So, if you are not getting enough UVB, then you need prescription or over-the-counter Vitamin D supplements. Now, there are 2 types of Vitamin D supplements, D2 and D3. My PCP didn’t seem to know much, so I had to research online for days to understand the difference and to figure out the right one for me. Look for my research findings in my next post.

Friday, October 1, 2010

Buying a Useful GPS on a Budget

Planning a road trip to Los Angeles, the first thing I knew I needed was a GPS. Usually my driving is limited to work commute and around the city. My trips being over the weekend, to save time I end up flying to the destination and then rely on local public transport or local friends. This time, I wanted to do a road trip! But, I often get lost when driving on unfamiliar roads, as a result of one wrong turn or just because I missed my exit.

I have AT&T cell phone and tried their turn by turn navigation. Unfortunately, I found a lot of patches on freeways and in national parks where coverage is weak and AT&T navigation is non-existent. So, I decided to invest in my first GPS with a daunting task ahead of choosing the right one for me. This blog entry is to help people like me, trying to figure out which GPS is right for them. The 2 conflicting concerns for me were:
  • Low budget: Don’t want to shell out too much money as technology changes rapidly and soon there will be a new feature that I would want. So, get a device that would serve my purpose for now and get it at a reasonable price
  • Useful GPS: Buy a GPS with positive user feedback’s and with features I know I should have. Concern here was that too low a budget would drive me down to a featureless GPS that will very soon become a junk.
I started by educating myself about the current manufacturers and features available in various GPS devices without paying too much attention to the prices. Amazon.com seems like a good place to start, so I started by searching for:
  • GPS & Navigation under Electronics
  • Avg Customer review of 3 Stars and above
  • Vehicle GPS
For this search, go here.

Manufacturers

It was easy to spot the best brand names as:
  • TomTom
  • Garmin
  • Magellan
So, I decided to stick to these brands for my research.


Features

Interface

  • Screen Size: Customer complained for screens less than 4’’ in size, so greater than 4’’ seemed like a good decision
  • Wide-screen: I would opt for it if the price doesn’t increase by more than $25
  • Touchscreen: Should have, otherwise it will just look like a huge PDA with lot of buttons, and touchscreen GPS aren’t that expensive anymore.
  • Voice recognition: Nah! Good to have, but so far I have had a hard time getting my pronunciations understood by machines. So, I wouldn’t pay more for this feature. Even if it works, it is just a convenience feature.
Street Names
Instead of “Take next left,” it would say “Take the next left on North First Street” - That would avoid a lot of confusion, most likely you would be relying on GPS in an unfamiliar area, so every little detail would help. This feature is must have.

Routes
Shortest based on time of the day - Could be very useful in avoiding busy traffic routes.
Best route for fuel economy - That would be cool. Go Green!
Multi-point routing - Go from starting point A to destination B, then to destination C, and so on. This feature is nice to have, but not necesarry. I won’t pay extra for this feature.

Lane Aware
Will tell you which lane you should be in to take the next turn or exit - Oh! This one is important, especially where a freeway forks into multiple other freeways. I know I need it. This feature is also called as Lane Assist.

Traffic
Some models come with free traffic updates. Traffic updates would be good for people who commute long distances during heavy traffic, like during commute hours to and from work, and road-trips during peak traffic around long-weekends or holiday season. You could choose for subscription based traffic updates depending on how much use you have for it. I want this feature.

Map updates
Some models come with Free Lifetime updates, otherwise updates can be costly. But, how often do the roads change? It might be OK to just pay and update after couple of years, that is, if you are not ready to upgrade to a newer technology. With time, new models will at least have better accuracy, more features, and faster processors. GPS models with lifetime free updates are expensive, so I will skip this.

Other features
Speed Limit - will show speed limits for roads where you are. Not necesarry as for safe driving you should be reading the road signs anyway.
Bluetooth - if you want to make hands free call from your bluetooth enabled cell phone through GPS. I would rather use my cell phone on speaker or use a separate bluetooth device just for cell phone.
FM transmitter - to have GPS hooked to the Car speaker system, a nice to have feature if the volume of GPS is low or your car’s drive is noisy. However, customers have reported that it frequently mingles with the radio channels and is hard to tune.


Selection

Now that I understood the features GPS should have, I found the following charts that were very helpful in deciding the models I was interested in:
  • Which Garmin Nuvi is right for you? - this link is from 2008, but still very helpful
  • Garmin Nuvi comparison chart
    • I was able to narrow it down to 14 models based on my requirement of “Speak Street names”, “Traffic”, and “Lane Assist”
    • Customer reviews suggested Garmin factory refurbished is very reliable and you get 60 days for free map and software updates, so I looked for the lowest price on factory refurbished version of the 14 models
    • The W and T notations in model number stand for Widescreen and Traffic update free for lifetime, respectively. Make sure you look at prices of the correct model number
    • Looking at the prices and available features on the 14 models, a price under $150 seemed reasonable for a good GPS
    • At the time, I narrowed down my interest to 755T (most features), 1350T(good price)
    • If they seem out of your budget, you may have to let go of some features that are less important to you. Like, nuvi 265T seems like a popular product without Lane assist feature.
    • Update Sep 2011: A new nuvi with most desirable options and free lifetime maps and traffic is 1450LMT for about $150 for new.
  • TomTom comparison chart
    • XL340T, XXL 540T
    • Similar products to the selected Garmin products above
    • If you are not comfortable with Garmin’s refurbished models, go for these TomTom’s new (non-refurbished) for about the same price.
    • Otherwise, Garmin’s customer satisfaction is a tad bit higher, so I am going for Garmin 1350T (refurbished) at this time
  • Magellan comparison chart
    • Cusomter reviews in general appeared lower than the Garmins
    • Factory refurbished is not as reliable as that of Garmin, so overall seemed pricier. Also, the traffic update is free for only 3 months and $40 per year thereafter

Deal Hunt

Once you have narrowed down to 3-4 models, it is time to hunt for deals. The best deal I found was on refurbished 1350T on Radioshack, so ordered one. My favorite utility and site to help you find lowest prices around: