Numbers Game: Answer

According to a 2007 study published in Health Economics, the percentage of high schools in the United States offering physical education on a daily basis declined from 41.6 percent in 1991 to 28.4 percent in 2003.

In that same time period -- in which massive budget cuts caused many school districts to succumb to dire economic conditions -- the number of vending machines in high schools increased by almost 100 percent.

You don't need an 'A' in algebra to figure out that is a worrisome equation.

Numbers Game: Fleeting Fitness

According to a 2007 study published in Health Economics, the percentage of high schools in the United States offering physical education on a daily basis declined from 41.6 percent in 1991 to __________ percent in 2003.

a) 34.9
b) 38.2
c) 28.4
d) 30.7

Leave your guess in the "comments" section and come back on Tuesday for the answer.

In The News: Genetics? Environment? Why Not A Little Bit Of Both?

Much like certain areas of sociology and psychology, the question of “nature versus nurture” permeates nutrition – or at least the consistently hot button issue of obesity.

A new study published in the Archives of Internal Medicine gives both factors the attention they equally deserve.

The end result?

“Vigorous physical activity can help even people genetically prone to obesity keep the weight off.”

A team of researchers led by Dr. Soren Snitker of the University of Maryland and Dr. Evadnie Rampersaud of the University of Miami “focused their study on a group of 704 Old Order Amish men and women in Lancaster County, Pennsylvania.”

Okay, not the largest sample size, but that doesn't mean we can't extract some juice -- and talking points.

As it turns out, participants who had the obesity (FTO) gene and engaged in the least amount of physical activity were, not surprisingly, "significantly more likely" to be overweight or obese.

However, those participants genetically predisposed to obesity but physically active were not heavier than participants without said predisposition partaking in similar amounts of physical activity.

It’s worth pointing out that the most physically active genetically predisposed group was burning an additional 900 calories than their satient counterparts.

That’s another point for the “calories count” camp!

By the way, the physical activity did not involve treadmills, Stairmasters, Swiss medicine balls, or pullup bars -- just old-fashioned chores (i.e.: gardening, farming, and even working the land with horses and plough!).

Do you think this study can be considered relevant for us non-Amish folks?

You Ask, I Answer: Basal Metabolic Rate/Daily Caloric Intake

How can one correctly find their BMR and the calories intake needed for the day?

I have messed up my BMR with my undereating and am in almost malnourished state.

I want to increase my BMR and lose some fat.

From what I understand, maintenance and weight loss is figuring out the equation between calories intake and daily activity.

I just want to know how to estimate a calorie range I should go for and amount of exercise I need to do daily.

I am small - medium frame woman, 130 pounds, and 5' 4", with almost no muscle tone.

-- Mandy (last name unknown)
Halifax, Canada

I’m confused.

You claim to have messed up your basal metabolic rate due to undereating to the point where you are in a “malnourished state”, yet are looking to lose fat?

In any case, to answer your question – yes, weight loss and maintenance comes down to figuring out the net result of calories in (food) minus calories out (metabolism).

Our basal metabolic rate -- the amount of calories we burn off simply by existing -- is ultimately determined by a variety of factors, among them age, genetics, physical activity, dietary paterns, body composition, and hormonal activity.

This last point is especially important. Thyroxin, produced by the thyroid gland, plays a crucial role in metabolism.

In hypothyroidism, very little thyroxin in produced, and BMR is significantly lowered.

If you are cutting calories appropriately and upping physical activity for several weeks and see absolutely no changes, pay a visit to an endocrinologist and have your thyroid gland checked.

Thyroid issues apart, many people appear to forget that some of these factors change with time, age being the most obvious.

This is one reason why, as people age, they find that weight “creeps up on them.”

The 2,500 calories once needed to maintain weight can be too many -- and cause weight gain -- ten years later.

This is where knowing TDEE (total daily energy expenditure) also comes in handy.

TDEE lets you know how many calories you approximately burn each day on top of what your body uses up as a result of standard bodily processes.

So how do you determine all these numbers?

First, calculate your BMR.

You can easily find that out by plugging some basic numbers into Discovery Health’s BMR Calculator.

If you want to get slightly more technical, you can also use the Mifflin-St Jeor formula, developed in 1990, which goes something like this:

Male BMR = 10* (weight in kg) + 6.25* (height in cm) - 5* (Age)+ 5
Female BMR = 10* (weight in kg)+ 6.25* (height in cm) - 5* (Age) -161

NOTE: To convert pounds to kilograms, divide by 2.2 To convert inches to centimeters, multiply times 2.54.

Prior to this, the Harris-Benedict formula (created in 1919) was used. While useful, Mifflin-St.Jeor results in more accurate numbers.

Ok, now: to calculate TDEE multiply your BMR by:

1.2 if you perform little to no physical activity
1.38 if you perform light physical activity a few times a week
1.55 if you perform moderate physical activity at least 3 times a week
1.725 if you perform intense physical activity on a daily basis
1.9 if you perform intense physical activity several times a day or have a very physically demanding job.

Whatever number you get is how many calories you need to maintain your desired body weight.

If you wish to lose -- or gain -- weight, simply subtract – or add – fifteen percent to that figure.

By consuming fifteen percent less calories and increasing your physical activity, you will certainly shed weight.

The fact that you mention having “no muscle tone” is significant, since increasing lean muscle mass is a sure-fire way to speed up metabolism.

This is why weight-bearing exercises are highly recommended -- they help with bone density and metabolism.

Alas, weight loss comes back to the tried and true advice of “eat less, move more.”

Simply Said: Cholesterol (Part 1)

Welcome to yet another new section of the Small Bites blog. "Simply Said" will help you understand confusing or overwhelming nutrition topics.

We begin with cholesterol. Our livers and cells produce about 80% of our body's cholesterol, a precursor to hormones like estrogen and testosterone and necessary for producing vitamin D out of the sunlight that hits our skin. That being said, cholesterol is not essential (meaning it is not necessary to get additional amounts from our diet).

There are four types of cholesterol, but the two you want to think about are low density (LDL) and high density (HDL). The four variations combined make up what is known as your total cholesterol.

LDL is the bad (or "lame") cholesterol. What's so bad about it? Well, the higher your LDL cholesterol, the higher your risk of strokes, heart attacks, and blood clots.

Why is this? LDL cholesterol ends up being deposited on the walls of our arteries, where it turns into hard plaque and restricts bloodflow.

HDL is the good (or "healthy") cholesterol that helps prevent plaque deposits by taking them to the liver for processing and removal when it spots them.

If your body were a town, LDL would be the litterbugs and HDL would be the sanitation workers.

Now, it is true that genes play a somewhat significant role in this. Some people -- no matter how healthy they eat -- have high levels of LDL, while others can go through life eating junk and still boast high HDL numbers.

Although the drug companies would love for all us to be on statins (cholesterol-lowering medication), the majority of us are in that middle area where our cholesterol profiles can be modified by diet.

Let's get this straight once and for all. It is not cholesterol in foods that raises our bad cholesterol, but saturated fat, found only in animal products (except those that are non-fat). So, when a package of bread boasts a "cholesterol-free" label on it, you can reply back, "well, duh!" and dismiss it as semi-dishonest marketing rather than groundbreaking nutritional information.

So how do you lower cholesterol? Physical activity is a must, but when it comes to food, your best weapon is soluble fiber (found in fruits, vegetables, nuts, and oatmeal), which bundles up and flushes out excess cholesterol.

(Note: physical activity does not have to mean a busy gym or loud spinning class. Simply increasing the distance you walk every day is enough to have an effect on your cholesterol levels).

Back to the nutrition factor. Going low-fat is NOT the answer to lowering your cholesterol. Rather, you want to go smart-fat. Monounsaturated fats (found in olive oil, walnuts, almonds, hazelnuts, sunflower seeds, avocados, and flaxseed) are helpful at maintaining our good cholesterol levels (a low-fat diet can actually lower it). Remember, the goal isn't just to lower bad cholesterol, but to increase the good one, too.

Tomorrow we'll finish up this segment with some numbers to help you make sense of your next blood lab results.