A PROACTIVE APPROACH TO HEALTH AND PERFORMANCE—NUTRIENT AND BLOOD TESTING
DAWN WEATHERWAX, RD, CSSD, ATC, CSCS
I
GENERAL BLOOD MARKERS
red and white blood cells, the metabolism, and oxygen delivery
to the tissues (9). It also impacts the function of the brain and
central nervous system. Signs of constipation, fatigue, loss of
appetite, memory loss, shortness of breath, and weakness are
all side effects of vitamin B12 deficiency. Declining vitamin B12
numbers can be linked to low stomach acid, excess alcohol intake,
gut inflammation, medications, pernicious anemia, post-surgical
malabsorption, and vegetarianism (10,22). A study showed that
40% of people between the ages of 26 and 83 had B12 levels
in a range at which many experienced neurological symptoms,
and another 25% had low or outright deficiency (11). The most
unpredicted outcome was the similarly low levels found in younger
people when compared with mature adults (11). Animal products,
including meat, poultry, fish, seafood, eggs, and dairy products are
excellent sources for vitamin B12 (24).
Fasting Glucose: The body uses glucose for energy. The body must
keep blood glucose in a tight range. Approximately 25% of those
who have an ideal bodyweight and composition still show prediabetic numbers (7). Chronic stress or poor sleeping practices
can also impact blood sugar levels in a detrimental way (6). If
fasting glucose numbers are too high or too low there are negative
consequences including eye, heart, kidney, and neurological
damage (19). According to the American Diabetes Association,
a fasting blood glucose level between 70 and 100 milligrams per
deciliter is considered normal (1).
Vitamin D: Vitamin D is a secosteroid, which is a derivative of a
steroid with a broken ring. It functions as a modulator for as many
as 1,000 genes; is involved in calcium homeostasis, bone health,
immunity, inflammatory intonation, and skeletal muscle function;
and has a potential impact on training and performance of athletes
(5,14,17). The best indicator of vitamin D levels is to measure serum
25(OH)D, which is commonly done with a 25-Dihydroxyvitamin
D test . Generally, vitamin D levels range from 32 – 100 ng/dl on
most lab reports.
t is improbable to always know if physical condition and
performance is at an optimal state as some issues have
unspoken outcomes. However, the body’s system can be
observed by blood testing to help achieve desired results
whether training for a competition, pursuing an individual goal, or
improving general health.
Besides looking at a lipid profile, another important step to
monitoring health is by establishing a baseline of values for fasting
glucose, ferritin, vitamin B-12, and vitamin D. For the purposes
of this article, these are the four blood profiles that will be
emphasized. Next comes knowing what the standard values are
and then aiming for peak levels, if appropriate.
Ferritin: Ferratin is a protein found mostly in the liver, skeletal
muscles, spleen, and bones. It stores iron in these areas so the
body can use it in the future. The preponderance of iron stored
in the body is found in ferritin. Because of this, the ferritin test is
often the preferred measurement to determine the amount of iron
in the body (4,20). At least 25% of any group of athletes can be
expected to exhibit low ferritin levels without being anemic (18).
Athletes who are most susceptible are ones with a low dietary
iron intake, menstrual losses, and high training levels. Low ferritin
levels may lead to anemia, extreme fatigue, impaired cognitive
performance, suboptimal metabolism, susceptibility to infection,
and compromised immune system and brain development (3,8).
The range of ferritin levels that is considered “healthy” remains a
controversial topic since recent studies have suggested that even
non-athletes may need more than previously thought (12).
Many authorities recommend iron supplementation for
hypoferritinemic individuals (16,23). Besides supplementation,
8 – 32 mg of iron per day through dietary intake is suggested
pending on dietary practices. Too much iron intake can also be
harmful to individuals, so caution is advised to maintain healthy
levels. Good food sources of iron include liver, beef, chicken,
salmon, lentils, beans, potatoes, quinoa, spinach, broccoli,
apricots, potatoes, pumpkin seeds, thyme, 80% dark
chocolate, molasses, tofu, and te mpeh.
One research study found that 72 out of 89 National Football
League (NFL) players (with an average age of 25 years old)
exhibited inadequate levels of Vitamin D (2). Deficiency may be
linked to an increase in muscle injuries (2). Out of these 89 NFL
football players, 27 players had deficient levels (<20 ng/dl) and 45
had insufficient vitamin D levels (20 – 31.9 ng/dl). Sixteen out of
the 27 players suffered a muscle injury with a mean vitamin D level
of 19.9 ng/dl. Possible signs of low vitamin D levels are fatigue,
achiness, and compromised immune system. The goal is to strive
for 200 international units (IU) of vitamin D a day from food and
the rest from ideal sun exposure (15). Additional supplementation
may be needed if an inadequate amount of sun exposure is not
obtained. Fatty fish (e.g., mackerel, salmon, sardines, oysters,
catfish, and tuna), fortified milk, egg yolks, fortified mushrooms,
and certain brands of margarine, yogurt, and cereal are reputable
sources for this vitamin (21).
VALUE OUTCOMES
All individuals with desirable values should continue to monitor
their numbers over the years. Always get a copy of lab results and
file them away for comparison. If any numbers seem irregular or
suboptimal, it is highly suggested to seek out help from a sports
dietitian, qualified nutritionist, or other health professionals.
Vitamin B12: Vitamin B12 is a water-soluble vitamin that plays
an important role in the body. It helps with the formation of
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