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O B ESI T Y
Weighty
Matters
Obesity has been linked to neurologic problems such as migraine,
dementia, and sleep apnea. Our experts review the evidence
and offer advice for getting weight under control.
T
hirty-five percent of Americans tip the scales into the
obese category, according to the US Centers for Disease
Control and Prevention (CDC). This public health crisis affects rates of heart disease, type 2 diabetes, and
some forms of cancer. Recently, that list of health problems has
grown longer as scientists have discovered a connection between obesity and neurologic conditions such as obstructive
sleep apnea, migraine, depression, Alzheimer’s disease, narcolepsy, and even carpal tunnel syndrome. What’s more, excessive
weight has been identified as a risk factor for cognitive decline
later in life.
In a 2009 study of 2,798 people published in the Archives
of Neurology, researchers from the University of Washington in
36 NeurologyNow •
FEBRUARY / MARCH 2016
Seattle reported that people who were obese at midlife had a 39
percent higher risk of developing dementia later in life than people
of a normal weight, based on their performance on various neuropsychiatric tests and magnetic resonance imaging scans. A study
published last April in Neurology found that obesity was associated with a higher rate of mild cognitive impairment, delayed
logical memory (the ability to recall a narrative story after a time
delay), and depression, among 397 older adults who were given
a battery of neuropsychological tests.
“Obesity impacts your general health, and your overall
health can affect your brain health and function,” says Jennifer
Molano, MD, FAAN, an associate professor of neurology and
rehabilitation medicine at the University of Cincinnati College
N E U R O LO GY N OW. CO M
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O B ESI T Y
EXCESS POUNDS AFFECT SLEEP
TIM POWELL
Current age: 50
Highest weight: 290 lbs
Current weight: 211 lbs
Highest BMI: 38
Current BMI: 28
Largest waist size: 48"
Current waist size: 35"
of Medicine. “To make sure your brain is healthy, you need to
make sure your body is healthy—and weight management is an
essential part of that.”
COURTESY TIM POWELL
BMI BENCHMARK
These days, a healthy weight is defined as a body mass index (BMI) between 18.5 and 24.9, according to the CDC. An
adult who has a BMI between 25 and 29.9 is considered overweight. Obesity is defined as having a BMI of 30 or higher,
and extreme obesity (formerly called morbid obesity) is defined as having a BMI of 40 or higher.
The point at which excess weight increases the risk of developing neurologic disorders varies from one condition and
individual to another and is based on genetic factors, underlying health conditions, lifestyle factors, and other considerations. But for many disorders, the risk begins to rise precipitously at a BMI of 30, Dr. Molano says. (Your doctor can chart
your BMI based on your height and weight, or you can do it
yourself at bit.ly/BMI-calc.)
N E U R O LO GY N O W. CO M After years of sleeping poorly and waking
up feeling tired in the morning, Tim Powell,
who is 6’1” and weighed 288 pounds in October 2013, went to his doctor at his wife’s
urging; she suspected he had sleep apnea
because of his loud snoring. “I had a general
lack of energy and regularly had to catch myself from falling asleep behind the wheel,” recalls Powell, a software project manager and
father of five in Salt Lake City. “I remember
feeling foggy and not being able to focus.”
After an overnight sleep assessment, Powell was diagnosed with sleep apnea, a potentially serious disorder in which a person
repeatedly stops breathing or breathes very
shallowly for seconds to minutes at a time,
then resumes breathing (often with a loud
snort, gasp, or choking sound) throughout
the night. Powell’s doctor thought his sleep
apnea was caused or exacerbated by his excess weight. Because he didn’t want to rely
on a machine or device to keep his airways
open while he slept, Powell, now 50, says
“that [diagnosis] was the tipping point for
me to improve my health.”
SLEEP APNEA AFFECTS WEIGHT
What Powell didn’t know is that his sleep apnea could have been
contributing to his excess weight, and vice versa. “People who
don’t get enough sleep experience neurochemical changes, including an increase in stress hormones such as cortisol, which can
lead to weight gain, elevated blood glucose, and insulin resistance
[a precursor to diabetes],” explains Todd J. Swick, MD, FAAN, an
assistant clinical professor of neurology at the University of Texas
School of Medicine in Houston. In fact, the relationship between
obesity and sleep apnea is a tricky two-way street. “The more obese
you are, the worse your sleep apnea gets,” Dr. Swick says, “and the
worse your sleep apnea gets, the more obese you become.”
With untreated sleep apnea or sleep deprivation of any kind,
levels of ghrelin, an appetite-regulating hormone, increase. Elevated ghrelin levels increase appetite, which can lead to weight
gain, notes Alon Avidan, MD, MPH, a professor of neurology
at the University of California, Los Angeles (UCLA) and director of the UCLA Sleep Disorders Center. “From there, the cycle continues,” with a revved-up appetite causing weight gain,
weight gain exacerbating sleep apnea, and so on.
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O B ESI T Y
“
The more obese you are the worse your sleep apnea
gets, and the the worse your sleep apnea gets,
the more obese you become.
­—TODD SWICK, MD, FAAN
NEUROTRANSMITTERS AND NARCOLEPSY
The basic mechanism linking obesity with obstructive sleep apnea
is largely anatomical. “The increased BMI and the effects of gravity
make it more likely for the tissues in the back of the throat to collapse, causing the airways to close up while you’re sleeping,” Dr.
Molano explains. But, she adds, the relationship between excess
weight and other neurologic disorders isn’t so easily explained.
Depending on the condition, various obesity-related physiological factors may be at work. For example, obesity is also
a risk factor for narcolepsy, a chronic neurologic disorder that
causes severe daytime drowsiness and sudden attacks of sleep
during waking hours, Dr. Avidan says. This may be related to
levels of a neuropeptide called orexin or hypocretin, which
regulates alertness, wakefulness, and appetite. Low levels of
orexin are associated with both obesity and narcolepsy. In a
2011 study in the Journal of Sleep Research, for example, investigators measured orexin levels in 70 people with narcolepsy
and found that the severity of excessive daytime sleepiness
was associated with an orexin deficiency. As far back as 2000,
in a study in The Lancet, researchers noted that people with
narcolepsy have a higher BMI than the general population.
”
Teshamae Monteith, MD, chief of the headache division at the
University of Miami Miller School of Medicine. This state can
increase the number of inflammatory substances in the brain
such as calcitonin gene-related peptides, which are linked to
an increase in the frequency, severity, and duration of migraine
attacks. In addition, “obesity is associated with sympathetic activation of the autonomic nervous system—the fight-or-flight
response—which is linked with migraine,” Dr. Monteith says.
“It’s also linked to low levels of adiponectin, [a hormone] related
to [increased inflammation] and pain.”
A meta-analysis published in the Journal of Headache and Pain
in March 2015 found that women who are obese have a 44 percent higher risk of migraine than women whose weight is in the
normal range. Additionally, overweight and obese women have,
respectively, a 39 percent and 75 percent higher chance of developing chronic migraines than women who are not overweight.
METABOLIC SYNDROME AND ALZHEIMER’S
Evidence suggests that those who develop metabolic syndrome
have a higher risk of developing Alzheimer’s disease. The syndrome is characterized by a waist circumference of 40 inches
or more for men and 35 inches or more for women plus two
THE HORMONE CONNECTION
of the following: elevated blood pressure (130/85 or higher
Scientists now know that excess body fat isn’t inert. It’s actu- without taking medication for hypertension), high triglycerides
ally quite active, and depending on its location it can set off (150 mg/dL or higher), low HDL or “good” cholesterol (below
a hormonal cascade of detrimental effects. In particular, in 40 mg/dL for men and below 50 mg/dL for women), and high
people with central or abdominal obesifasting blood sugar (100 mg/dL or higher).
ty (the classic apple-shaped pattern), the
“Obesity quadruples the risk of develBMI BREAKDOWN
fat surrounding organs can raise levels of
oping Alzheimer’s,” says Gary Small, MD,
stress hormones such as cortisol, promote
director of the UCLA Longevity Center
These days, a healthy weight is
systemic inflammation, increase oxidative
and coauthor of The Alzheimer’s Prevention
defined less by the numbers on
stress (rust-like damage that’s caused by unProgram (Workman Publishing Company,
a scale than by body mass index
stable molecules called free radicals), and
2011). He cited a 2011 study of 8,534
(BMI). According to the US Cencreate insulin resistance (a reduced retwins published in Neurology that found
ters for Disease Control, a BMI of
sponse to the hormone insulin, which
that obesity in midlife was associated with
between 18.5 and 24.9 is healthy
makes blood sugar rise). Each of these
four times the risk of later developing defor adults. A BMI higher than
effects can harm the brain and neurologic
mentia, including Alzheimer’s disease and
24.9 breaks down as follows:
function.
vascular dementia, compared with a normal BMI. Excess belly fat, in particular,
25-29: Overweight
has been linked with an increased risk of
INFLAMMATION AND MIGRAINE
late-onset Alzheimer’s disease.
The underlying pathways connecting obe30-40: Obese
Even without metabolic syndrome,
sity with certain neurologic disorders are
people
who have insulin resistance or
more complicated in some conditions than
OVER 40: Extremely obese
type
2
diabetes—both
of which can stem
in others. The association between mi(formerly called
from
being
overweight
or obese—may be
graine and obesity, for instance, may stem
morbidly obese)
at
higher
risk
for
Alzheimer’
s disease. This
partly from the fact that obesity is considered a pro-inflammatory state, explains
may be due partly to increased inflamma-
42 NeurologyNow •
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N E U R O LO GY N OW. CO M
SHELLEY RAFILSON
Current age: 60
Highest weight: 229 lbs
Current weight: 130 lbs
Highest BMI: 41
Current BMI: 23
Largest dress size: 26
Current dress size: 8
tion, Dr. Small notes, but a 2015 study in Molecular Aspects of
Medicine suggested that type 2 diabetes and Alzheimer’s may
share genetic risk factors as well. Indeed, insulin resistance and
diabetes have been shown to cause changes in brain structure
and function that are seen with Alzheimer’s disease, injuring
neurons and causing abnormal growth patterns such as the formation of tau tangles and amyloid plaques, says Dr. Small.
COURTESY SHELLEY RAFILSON
A LINK TO PEDIATRIC MULTIPLE SCLEROSIS
Some research suggests that obesity may be a risk factor for pediatric multiple sclerosis (MS), too. Scientists from Kaiser Permanente Southern California found that obesity was associated
with a significantly increased risk of MS among girls between
the ages of 11 and 18. The study, published in Neurology in
2013, showed that overweight girls had one and a half times
the risk of developing MS compared with their normal-weight
peers. Moderately obese girls had 1.8 times the risk, and those
who were extremely obese (meaning their weight was off the
charts for their age and sex) had nearly four times the risk. The
researchers theorized that high estrogen exposure and the lowgrade inflammatory state that occurs with obesity may accelerate the onset of MS.
“It has been more difficult to link obesity, independent of cardiovascular risk factors, to the risk of developing MS in adults,”
says Dennis N. Bourdette, MD, FAAN, an endowed professor
in the department of neurology at Oregon Health & Science
University in Portland. “However, obesity appears to increase
fatigue in people with MS and compounds other symptoms of
MS. So an MS patient who is obese and develops mild leg weakness, for example, will have a lot more problems adapting to
that weakness than someone who maintains a normal weight.”
MEDICATION AND WEIGHT GAIN
Certain antiseizure drugs and corticosteroids, as well as antidepressants used to treat certain forms of pain, and beta blockers
N E U R O LO GY N O W. CO M prescribed for migraines, can cause extra pounds
to creep on, either because they decrease metabolic rate or stimulate appetite or both, notes Dr.
Monteith. “Not all patients are going to get that
effect, but some will,” she says.
Cynthia Fabian, who has epilepsy and sleep
apnea related to nocturnal seizures, is one of
them. “Depakote [divalproex sodium] has been
nothing short of a miracle for me in terms of
seizure control, but it hasn’t been without tradeoffs. I follow a 1,200-calorie diet and take at least
one class at the gym each day just to maintain my
nearly 200-pound frame,” says Fabian, 57, a teacher and writer
in Venice, FL.
At one point, Fabian switched to topiramate (Topamax), another antiseizure drug. While it helped her drop 60 pounds, it
didn’t control her seizures sufficiently. So she went back on divalproex sodium and regained the weight. In her view, the added
pounds have been a small price to pay for being able to drive and
have a normal, active life. “I remain positive and meditate nearly
every day,” she adds. “But it is difficult [for people] to understand
how someone who does not eat much still has a larger frame.”
THE WEIGHT LOSS BONUS
People who lose weight often see an improvement in their condition. Case in point: A 2011 study published in Cephalalgia
found that when obese premenopausal women with migraine
underwent bariatric surgery for weight reduction, the frequency
of their episodic migraines dropped from four a month to one
a month and their chronic migraine episodes decreased from
16.8 to 8.5 a month. What’s more, the attacks were shorter and
the women needed less medication to manage them.
Even habits that facilitate weight loss can improve neurologic disorders linked with obesity. For example, some studies
show that exercise can protect against migraine, says Dr. Monteith. A 2011 study of 91 patients with migraine published in
Cephalalgia found that exercising for 40 minutes, three times a
week, was more effective at reducing migraine attacks than taking topiramate. The forms of exercise that show the most benefit tend to be gentler, such as swimming or cycling, as opposed
to jarring, pounding activities such as aerobics or jogging.
LESS WEIGHT, MORE SLEEP
Just as sleep apnea can create an upward spiral of weight gain
and worse apnea, weight loss can reverse that cycle and lead to
better sleep and, in some cases, a remission of apnea. That was
the experience of Tim Powell, the father of five from Salt Lake
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O B ESI T Y
“
I decided it was time to turn my life around, and that’s
exactly what I did...[Now] I want to help others
learn from my experience.
­—SHELLEY RAFILSON
City. After revamping his diet and eating fewer refined carbohydrates, less sugar, fewer processed foods, and more vegetables, fruits, and healthy fats, and exercising for an hour a day
(30 minutes of cardio, 30 minutes of resistance training) five
or six days a week, he lost 77 pounds in seven months. His
snoring disappeared, along with any signs of sleep apnea, and
his blood pressure and cholesterol improved. “I have much
more energy,” he reports. “It’s been a huge difference.”
For those who don’t have the energy to lose weight, a
continuous positive airway pressure (CPAP) machine that
keeps airways open during sleep can help, says Dr. Avidan.
When the sleep disorder is well controlled, people may have
more energy to make the dietary changes and perform the
physical activities that will help them lose weight. Once they
start to lose weight, “the pressure on the CPAP machine can
be readjusted,” he says.
A TRANSFORMATION
Even for people who are obese and have more than one neurologic disorder, losing weight can make a tremendous difference. Shelley Rafilson, a singer and writer in Scottsdale,
AZ, has severe neuropathy, fibromyalgia, hypothyroidism,
and arthritis. While caring for her elderly father, she gained
100 pounds and developed sleep apnea, which took a further
toll on her energy, weight, and pain. When she found herself struggling to get off the floor after putting on her father’s
shoes, she decided to take action.
A few years ago, Rafilson went on a 1,200-calorie diet,
started walking for exercise, and began weighing herself
once a week. “I decided it was time to turn my life around,
and that’s exactly what I did,” says Rafilson, now 60. It was
difficult, she says, but she persevered, and over the span
of two years she lost more than 100 pounds, kicked her
reliance on pain medications, and wrote and self-published
100 Pounds to Happiness!, a book about her transformation.
“I want to help others learn from my experience,” she says.
Her take-home message? Losing weight is worth the effort
for an improved quality of life and a future of good health. As
Dr. Molano says, “What you do at midlife can have an impact
NN
on what happens later in terms of your brain health.”
44 NeurologyNow •
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”
Lose Weight, Gain Health
Dropping pounds can help you reclaim
and protect your health.
M
any of the negative health effects of obesity can
be reversed by losing weight. The challenge,
of course, is getting started. We asked several
weight-loss experts for advice.
START WITH CALORIES. “Limiting calories is much more
effective for initial weight loss than exercising, so don’t
worry if your [condition] limits what you can do in terms of
physical activity,” says Lawrence Cheskin, MD, director of
the Johns Hopkins Weight Management Center in Baltimore.
Many weight-loss experts, including Dr. Cheskin, recommend reducing your calorie intake by 500 to 750 calories a
day to lose one to one-and-half pounds a week.
AVOID REFINED CARBOHYDRATES. It’s not just the quantity
of calories that count; quality matters, too. “Most people
consume more carbohydrates than they need,” says Molly
Kimball, RD, nutrition program manager of the Ochsner
Health System’s Elmwood Fitness Center in New Orleans. She
advises cutting down on refined carbohydrates and focusing
on eating more fiber and whole grains like quinoa and brown
rice, lean protein like skinless poultry and fish, vegetables,
and spices and aromatic herbs.
CHOOSE BRAIN FOOD. Consuming antioxidant-rich berries,
plums, cherries, apricots, grapes, broccoli, sweet potatoes,
bell peppers, spinach, and tomatoes can help protect your
brain from harmful free radicals that cause wear and tear
on your cells, explains Gary Small, MD, director of the UCLA
N E U R O LO GY N OW. CO M
Longevity Center. The omega-3 fatty acids in fish such
as salmon, mackerel, tuna, sardines, and anchovies can
reduce harmful inflammation in your body.
EAT SMALLER PORTIONS. Be mindful of the size of your
meals. If you don’t prepare your own food, make sure
people involved in your care adhere to your nutritional
goals, Kimball adds.
ENLIST A BUDDY. Get plenty of sleep and learn to manage stress without turning to food. “It helps if you have
a friend for support,” Kimball says. “That buddy system
helps keep up motivation.”
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SET A CALORIE BUDGET. Pick your target weight, then
determine how many calories you need to reach it. If, for example, you want to weigh 150 pounds and have no physical
limitations, allow yourself 10 calories for each pound for a
total of 1,500 calories per day, says Kimball. (If you exercise
more than an hour a day, you may need more calories.)
To track your calorie intake, Kimball recommends using a
smartphone app like MyFitnessPal. If you have physical
limitations or mobility problems, you may need to decrease
your daily calorie allotment by 10 to 25 percent while trying
to lose weight, depending on the extent of your limitations,
Kimball says. If you don’t want to count calories, Kimball
recommends limiting starchy carbohydrates of all types,
including whole grains, and focusing on lean proteins,
vegetables, and small amounts of healthy fats.
HONOR YOUR HUNGER SIGNALS. Get in the habit of
listening to your body and paying attention to when
you’re truly physically hungry and when you simply have the urge to eat, Kimball suggests. If you’re
hungry, you should eat healthy foods but stop eating
before you feel completely full. If you have an urge to
eat, identify what’s causing it. If it’s loneliness, for
example, call a friend. If you’re feeling sad, listen to
upbeat music. If you’re tired, take a nap.
INCORPORATE AEROBIC ACTIVITY. Besides helping you
burn extra calories during a workout, exercising helps
shed body fat, add lean muscle (which will help you burn
more calories all day), and increase your cardiovascular
fitness, Dr. Cheskin says. If you’re new to exercise and
have no physical limitations, start with 10 to 20 minutes
a day and build up from there. Eventually, the goal is
to do at least 45 minutes of aerobic exercise—such as
N E U R O LO GY N O W. CO M walking, swimming, bicycling, or using the elliptical machine—most days of the week. “Cardio exercise is good
for your heart and vascular health, your mood and stress
levels,” Kimball says.
ADD STRENGTH TRAINING. Working out with resistance
bands or weights twice a week builds lean muscle,
increases your strength, and helps you with activities of
daily living. “Increasing lean muscle can raise your resting
metabolic rate: One pound of muscle can burn approximately seven calories [per day], so adding 3 to 4 pounds
of lean muscle, which is very reasonable within 12 to 14
weeks in a proper strength training program, can increase
your ability to burn calories when you aren’t exercising by
up to 30 calories a day,” says Pete McCall, MS, a professor
of exercise science at Mesa College in San Diego.
ACCOMMODATE PHYSICAL LIMITATIONS. If you have
mobility problems, start by doing what you can three
times a week and building from there. And consult your
neurologist about any possible limitations. “Just getting
up and moving for five minutes at a time with two to
three 10- to 15-minute intervals throughout the day for
activities such as walking, climbing stairs, or simply
standing can improve your ability to burn calories,” says
McCall. Find an activity you enjoy—whether it’s walking, riding a stationary bicycle, or doing exercises in a
pool—and make it a habit. “Start slowly, then increase
intensity and frequency,” McCall advises.
WORK WITH A THERAPIST. If you have limited use of
your legs or difficulty gripping things, consider teaming
up with a physical or occupational therapist who can
show you how to use various exercise machines and
pieces of equipment. For example, some people may
benefit from using a hand cycle, which is powered by
the arms instead of the legs, or resistance bands that
are attached to a wall or door, or Velcro weights for the
wrists or ankles for strength training. “Do anything to
move your muscles and get your heart rate up so you can
burn more calories,” Kimball says.
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