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 through a phenomenon known as metabolic adaptation. 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 than what was originally lost, ultimately with fewer calories consumed.
In 1990, I worked as a peer educator at 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 luxusconsumption
- 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 were 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 are 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 calories 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 lose fat and maintain lean body weight.
Comparing metabolism to a campfire has been used as an analogy. If a fire is not fed 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 fed regularly.
Since I am not a registered dietitian, I cannot personally recommend a regimen for you due to your medical condition. I would recommend seeking the advice of a registered dietitian who is familiar with exercise and concepts such as Thermogenesis 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 you 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 an y medical concern. Consider referring your clients to a registered dietitian for individual dietary advise related to medical issues.