Starvation Effect
I've heard about the "starvation" effect (loosely
- and most likely incorrectly) defined as the inability to lose
weight when one's caloric intake is too low. For example, I would
guess my "base metabolic" calorie requirements are
about 1,800 to 2,000 per day; I'm actually consuming between
1,100 to 1,300 per day. I work out five nites per week, and since
I've had some cardiac artery problems, I do less than 12 grams
of sat. fat per day. However, I don't seem to be able to lose
weight or make much inroad on my "visceral" belly fat...drives
me nuts!! Any truth to the "starvation effect"?
The
metabolism seems to decrease over the years, particularly when
meals are skipped or calorie restrictive diets are implemented.
The body adapts to this stress with a biological protective mechanism;
the metabolism decreases. Once more calories are reintroduced,
more body fat may be gained than was originally lost. This attributes
to what is known as yo-yo dieting. The body gains back more fat
that what was originally lost, ultimately with fewer calories
consumed.
In 1990 I worked as a peer educator at the Kansas State University
Student Health Center. I had two particular cases where clients
wanted to lose fat but their caloric intake was only half what
was estimated for their activity and weight. Dr. Katherine Gruenwald,
KSU Foods and Nutrition Department assisted me in developing
a dietary approach to increase their metabolism which allowed
them to double the calories they consumed and loss body fat.
This was partly accomplished by eating 3 meals and 2 to 3
snacks throughout the day. The type of food consumed is important;
a diet with plenty of fruits, vegetables, whole grains and lean
protein sources each meal and snack. Refined foods such as white
flour and sugar should only be consumed sparingly, if not at
all. See Dietary
Guidelines.
When combined with the introduction of an exercise program,
fat weight typically decreases and lean body weight increases.
Exercise needs to consist of both an anaerobic and aerobic type
activity like weight training and brisk walking. During this
transaction period, fat gain is minimal if non existent. The
extra calories are utilized:
- Energy during workouts
- Synthesis of lean body weight
- Energy expended at rest due to greater lean body weight
- Thermogenesis: increased body heat via luxusconsuption
- Increased activity during rest (i.e. fidgeting)
- Possible increase production of thyroid hormones
Many of these mechanisms are related. Incidentally, calorie
restriction has the opposite effect.
A similar case study was published
by Jampolis (2004). A 51 year old patient complained of a 15
lb weight gain over the last year despite beginning a strenuous
triathlon and marathon training program (2 hours per day, 5-6
days per week). A 3 day diet analysis estimated a daily intake
of only 1000-1200 Calories. An indirect calorimetry revealed
a resting metabolic rate of 950 Calories (28% below predicted
for age, height, weight, and gender). After medications and medical
conditions such as hypothyroidism and diabetes where ruled out,
the final diagnosis was over-training and undereating. The following
treatment was recommended:
- Increase daily dietary intake by approximately 100 Calories
per week to a goal of 1500 calories
- 32% protein; 35% carbohydrates; 33% fat
- Consume 5-6 small meals per day
- Small amounts of protein with each meal or snack
- Choose high fiber starches
- Select mono- and poly- unsaturated fats
- Restrict consumption of starch with evening meals unless
focused around training
- Take daily multi-vitamin and mineral supplement
- Perform whole body isometric resistance training 2 times
per week
After
6 weeks the patient's resting metabolism increased 35% to 1282
Calories per day (only 2% below predicted). The patient also
decreases percent fat from 37% to 34%, a loss of 5 lbs of body
fat.
Jampolis MB (2004) Weight Gain - Marathon Runner / Triathlete.
Medicine & Science in Sports & Exercise, 36(5) S148.
You can begin by calculating how many TOTAL Calories is recommended
for your weight and gender, see Estimated
Energy Requirements. Make sure you are eating appropriate
proportions of protein, fat and carbohydrates for your metabolism
and activity, see Food
Exchange Calculator.
Find someone to measure your body
composition every month to monitor progress and to make corrections.
Get an accurate body weight to calculate and track fat weight
and lean body mass.
After the metabolism is corrected, I recommend to only deliberately
decrease calories as a last resort. Make sure you are getting
the most you can out of exercise program and frequent feedings
before calorie restriction is re-implemented. Adjust the proportion
of macronutrients if necessary. If calories are decreased, decrease
the minimum number of calorie that will elicit fat loss, (ie.
100 Kcal or 250 kcal). Realize the body will again adapt to lower
calories and weight loss will plateau. The more the calories
are restricted, the lower the metabolism will decrease, making
it harder to loss fat and maintain lean body weight.
Comparing metabolism to a camp fire has been used as an analogy.
If a fire is not feed with wood regularly its heat dwindles.
If a large log is placed upon it, the fire takes some time to
consume it. A large log can be more readily consumed by a fire
that is feed regularly.
Since I am not a registered dietitian, I can not personally
recommend a regimen for you due to your medical condition. I
would recommend seeking the advise of a registered dietitian
who is familiar with exercise and concepts such as Thermogenisis
and the latest research on the Optimal
Macronutrients Ratios for Weight Loss. Many dietitians are
unfortunately still stuck in the dark ages and use the oversimplified
static model; energy in = energy out. The body is much more dynamic
and adaptive.
Although your peripheral body is lean, you will have to continue
to lower your overall body fat before your lose your belly. Interestingly,
abdominal fat is correlated with higher incidents of coronary
artery disease and Type 2 diabetes, and even mortality. Also
see Waist Hip Ratio
Calculator and Spot
Reduction Myth.
Hypothyroidism Thermogenesis Impairment
I have had a few clients with hypothyroidism. My wife even
takes medication for it. I also have a client that has had a
thyroidectomy. Can you tell me of dietary and exercise considerations
when working with someone with hypothyroidism. It seems they
are usually trying to lose weight.
Would they be unable to increase thermogenesis by increasing
their calories consumption back to normal since there production
of thyroxin is impaired? I forget exactly about the conversion
of T3 to T4, negative feedback loops, and so forth. Any suggestions
would be appreciated.
The only way you can treat/normalize hypothyroidism is by
giving thyroid hormone (eg: Synthroid, Armour) so that their
serum levels of TSH (Thyroid stimulating hormone), T3 and T4
levels are normal. It may take a few weeks/months to accumulate
a normal pool size, and playing around with different dosages
to get an individual's levels to hit in the right spot. Once
they are treated, everything is exactly the same and they can
do whatever they could before the thyroid problems.
So your question I guess has to do with what nutrition/exercise
things they can do while waiting for the supplementary thyroid
to normalize them....
There really is no good nutritional way to "treat/deal-with"
hypothyroidism. Just be aware that their metabolic rate will
be lower so they have to pay more attention to the quality of
their diet and not eat a lot of extra junk. I don't think eating
extra for thermogenesis is your best approach. Hypothyroids usually
gain weight (though mostly fluid). If there is anything they
can do about it (while waiting for the synthroid to take effect)
I would say get more exercise. They may not feel like doing it
because of the heavy sluggish feeling and maybe the apathy that
goes with it. Also of course it won't "cancel out"
the hypothyroidism. But exercise is the best thing they can do
to deal with the lowered metabolic rate, feeling cold, and fluid
retention. Certainly your clients should consult their physician
regarding any medical concern. Consider referring your clients
to a registered dietitian for individual dietary advise related
to medical issues.
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