Appendix C
KNOW YOUR IMPORTANT HEALTH NUMBERS
To feel better fast, you must know if your brain is working right, and then optimize it if it is not. To that end, it is critical to know your important health numbers. A fundamental business principle applies here: “You cannot change what you do not measure.” You should check these numbers on an annual basis and whenever you feel out of sorts.
Body mass index (BMI). This measurement is the result of comparing weight to height. An optimal BMI is between 18.5 and 25; the overweight range falls between 25 and 30; more than 30 indicates obesity; and more than 40 indicates morbid obesity. To determine your BMI, google “BMI Calculator” and fill in your height and weight. Take this number seriously, because being overweight or obese is associated with having a smaller brain, and when it comes to your brain, size matters! Plus, obesity increases the risk for Alzheimer’s disease and depression. In a new study, 40 percent of all cancers have been linked to excess weight.[463]
Blood pressure. Good blood pressure is critical for brain health. High blood pressure is associated with lower overall brain function, which means bad decision-making. The American Heart Association and the American College of Cardiology have revised their guidelines, which now means anyone with blood pressure of 130/80 millimeters of mercury will be diagnosed with stage 1 hypertension. Previously, a blood pressure of 140/90 was considered hypertension. (The category of “prehypertension” no longer exists.) That means more Americans than ever —half of all men and 38 percent of women, or 103 million people versus 72 million before this change —are now considered to have hypertension.[464] Here are the blood pressure numbers you should know:
- Optimal
- Systolic 90–120
- Diastolic 60–80
- Stage 1 Hypertension
- Systolic 130–139
- Diastolic 80–89
- Stage 2 Hypertension
- Systolic >/= 140
- Diastolic >/= 90
- Hypotension —blood pressure that is too low can also be a problem
- Systolic < 90
- Diastolic < 60
KEY LABORATORY TESTS
Laboratory tests provide another set of important numbers. Ask your health care professional to order them, or you can order them for yourself at websites like www.saveonlabs.com. If your numbers are abnormal, be sure to work with your health care professional to get them into optimal ranges. Here are the key lab tests that will provide insights into how well your body is functioning. All are blood tests unless otherwise indicated.
CBC (complete blood count). This blood test checks the health of your blood, including red and white blood cells. Low red blood cell count (anemia) can make you feel anxious and tired and can lead to memory problems. Enlarged red blood cells may mean you are drinking too much alcohol. A high level of white blood cells may indicate infection.
General metabolic panel with fasting blood sugar and lipid panel. This checks the health of your liver and kidneys, as well as your fasting blood sugar, cholesterol, and triglycerides.
Knowing your fasting blood sugar number is especially important.
- Normal is 70–100 milligrams per deciliter (mg/dL)
- Optimal is 70–89 mg/dL
- Prediabetes is 100–125 mg/dL
- Diabetes is 126 mg/dL or higher
Why is high fasting blood sugar a problem? Elevated blood sugar causes vascular (blood vessel) problems throughout your whole body, including your brain. Over time, blood vessels become brittle and vulnerable to breaking. High blood sugar leads not only to diabetes, but also to heart disease, stroke, visual impairment, impaired wound healing, wrinkled skin, and cognitive problems.
Cholesterol and triglycerides (fats) in the blood are also important, especially because they can negatively affect blood delivery to the brain. Cholesterol that is either too high or too low is bad for the brain. Higher cholesterol later in life has been associated with better cognitive performance,[465] longevity,[466] and a decreased risk of dementia. Normal levels are
- Total cholesterol: 135–200 mg/dL (below 160 has been associated with depression, suicide, homicide, and death from all causes, so 160–200mg/dL is optimal)
- HDL: >/= 60 mg/dL
- LDL: <100 mg/dL
- Triglycerides: <150 mg/dL
It is also important to know the particle size of your LDL cholesterol (ask your health care professional to order this test) because smaller particles are more toxic than larger ones. If your cholesterol numbers are not optimal and you wish to find out more, I recommend The Great Cholesterol Myth by Jonny Bowden, PhD, and Stephen Sinatra, MD.
Hemoglobin A1c, or HbA1c. This test, used to diagnose diabetes and prediabetes, is a measure of the average blood sugar levels for the prior two to three months. A result of 4–5.6 percent is normal for a nondiabetic; optimal is under 5.3 percent. A result in the 5.7–6.4 percent range indicates prediabetes. Higher numbers may signal diabetes.
Vitamin D. Low levels of vitamin D have been associated with obesity, depression, cognitive impairment, heart disease, reduced immunity, cancer, and all causes of mortality. The best blood test to get measures the 25-hydroxyvitamin D level. A normal vitamin D level is 30–100 nanograms (ng)/mL, with the most optimal range being 50–100 ng/mL.
Thyroid panel. Abnormal thyroid hormone levels are a common cause of anxiety, depression, forgetfulness, weight problems, and lethargy. Having low thyroid levels, or hypothyroidism, decreases overall brain activity, which can impair your thinking, judgment, and self-control. Low thyroid functioning can also make it nearly impossible to manage weight effectively. High levels (hyperthyroidism, less common than hypothyroidism) are associated with anxiety, insomnia, and feeling agitated. Healthy thyroid levels are
- TSH (thyroid-stimulating hormone): 0.4–3.0 IU/L
- Free T3: see normal ranges for the individual laboratory you use.
- Free T4: see normal range for the individual laboratory you use.
- Thyroid antibodies: thyroid peroxidase antibodies: < 9.0 IU/mL and thyroglobulin antibodies: < 4.0 IU/mL
Unfortunately, there is no single symptom or test result that will properly diagnose hypothyroidism. The key is to gather your symptoms and your blood test results and consult with your physician. Symptoms of low thyroid include fatigue, depression, mental fog, dry skin, hair loss (especially the outer third of your eyebrows), feeling cold when others feel normal, constipation, hoarse voice, and weight gain.
C-reactive protein (CRP). This test measures the inflammation in your body. Inflammation comes from the Latin word for “to set on fire” and describes a process associated with many chronic illnesses, including depression, dementia, and pain syndromes. A healthy CRP range is 0.0–1.0 mg/dL.
Homocysteine. Elevated homocysteine levels (>8 micromoles/liter) are associated with atherosclerosis (hardening and narrowing of the arteries) and an increased risk of heart attack, stroke, blood clot formation, and possibly Alzheimer’s disease. Homocysteine is also a sensitive marker for a folate deficiency (folate is required for producing DNA and other genetic material).
Ferritin. This is a measure of iron stores. High levels are associated with inflammation and insulin resistance. Low levels are associated with anemia, restless leg syndrome, ADHD, and low motivation and energy. A level of 50–100 ng/mL is ideal. Women often have lower iron stores than men, due to blood loss from menstruation. Some theorize that this is one of the reasons that women tend to live longer than men. If your level is low, consider taking iron. If it is high, donating blood may help.
Free and total serum testosterone. For both men and women, low levels of testosterone have been associated with low energy, cardiovascular disease, obesity, low libido, depression, and Alzheimer’s disease.
Normal levels for adult males are
- Total testosterone: 280–800 ng/dL; optimal is 500–800 ng/dL
- Free testosterone: 7.2–24 picograms (pg)/mL; optimal is 12–24 pg/mL
Normal levels for adult females are
- Total testosterone: 6–82 ng/dL; optimal is 40–82 ng/dL
- Free testosterone: 0.0–2.2 pg/mL; optimal 1.0–2.2 pg/mL
Estrogen and progesterone for women. Depending on the circumstances, these are measured in blood or saliva. Menstruating women are usually tested on day 21 of their cycle, while postmenopausal women can be measured anytime. Estrogen is responsible for vaginal lubrication and helps with libido and memory —and so much more. Progesterone calms emotions, contributes to a restful sleep, and acts as a diuretic. See the normal ranges for the individual laboratory you use.
Omega-3 Index. This measures the total amount of omega-3 fatty acids EPA and DHA in red blood cells and directly reflects their levels in the brain. The test is a clinically validated biomarker of the health of your brain. Your risk of cognitive decline rises by as much as 77 percent when your Omega-3 Index is low. Aim for a level above 8 percent.
Knowing and optimizing these numbers is critical to helping your brain work right. If any of them are abnormal, the function of your brain can be troubled too. Work with your health care provider to help get these numbers into the most optimal range possible.
Get in the habit of checking out your important health numbers on an annual basis.