11 June 2008
Our body tends to cook up mysterious reasons to hoard fat. And junking the junk may not be the only way to beat it. Sangita Sultania asks experts the hows and whys
There are no shortcuts to success, and it applies as much to the battle of the bulge. The human body is more intelligent than we often think. If you believe you are outwitting your gym buddies by starving yourself into shape, the body perks its antennas and goes on a hoarding drive, more so after you’ve gone back to consuming human portions of food. The result: you end up with more fat than you started off with.
“Let’s understand the science of metabolism first”, says Eileen Canday, chief dietician, Breach Candy Hospital Trust. “Fat storage in a non–obese adult appears to be regulated in a manner that preserves a specific body weight.
Deliberated efforts to starve or overfeed are followed by rapid return to the original body weight”, she explains.
The component of energy expenditure is expressed as resting metabolic rate (RMR), ie the energy expended in voluntary activity and that required to digest food, Eileen tells us. When the body is suddenly deprived of adequate energy, the RMR adapts to conserve energy against the unpredictable future by dropping rapidly. When adequate food intake is restored, the RMR returns to baseline levels. So even if the body starves itself for a short time or overeats occasionally, the RMR helps regulate the fat content in the body. In case of prolonged starvation, the RMR adapts itself to conserve this energy. “And the body will continue in this mode for quite some time even after the person resumes a normal diet, as the body is extra alert now and is not sure when it will be subjected to starvation again”, says Eileen.
Also, when one switches to a low carbohydrate diet, for example the Atkins diet associated with rapid weight loss, the body initially breaks down glycogen and protein to glucose to maintain the blood glucose level. Both glycogen and protein have associated water which is lost from the body when they are broken down. This diuresis contributes to the large weight loss seen early in the course of low calorie, low carbohydrate diet.
“These diets also produce ketosis which may induce anorexia and hence compliance. As about 50 to 60 per cent of the body weight comprises of water, this causes rapid weight loss. Once the body goes off this diet, the body acts like a sponge and tends to store as much fat and energy as it can”, says Eileen. To lose half a kilo of fat, the body needs to burn 3,400 KCals. There is no other healthy alternative to lose weight, she stresses.
Fluid and fat retention are connected. “Certain hormonal imbalances in the body, for example during menopause, causes the body to retain fluids and give rise to a bloated feeling and look”, says Ramanjit Kaur Ahluwalia, nutritionist with Talwalkar’s. Intake of a high sodium diet also leads to fluid retention, especially in the abdomen region, one of the reasons of the ubiquitous ‘Pot belly’. “Heavy consumption of confectionaries, canned and salty foods lead to fluid retention too”, Ramanjit says.
Irregular eating habits also trick the body into hoarding mode. Diet–induced ‘Thermogenesis’ (energy required to digest food) is higher after a morning snack than after afternoon or night, suggesting that the effect of thermogenesis declines as the evening progresses. “If you are prone to skipping breakfast and opt for brunch instead, the body will find it more difficult to digest that food. Also, if you go hungry for a long time, you tend to overeat in the next meal and give in to cravings for the wrong kind of food”, Eileen cautions.
Irregular sleep patterns also causes the body to store fat. “Sleep deprivation causes the body to release a hormone Ghrelin, which promotes hunger. Also, people who stay up nights because of their professions, tend to indulge in less physical activity, and upon that, snack more”, says Eileen.
Stress causes a tendency to binge, especially on stress–relieving foods like chocolate to feel better. Secretion of epinephrine is increased during anger or fear or stress and subsequent glucose formation provides extra energy for crisis. “Serotonin, neuropeptide and endorphins are neurochemicals that are thought to be involved in feeding behaviours. Decreases in serotonin increase carbohydrate appetite”, Eileen informs.
Thyroid “The basal metabolic rate or the BMR is closely related to the thyroid. In case of hypothyroidism, when the body doesn’t produce enough thyroid hormones, one tends to put on weight as the BMR decreases. The effect is opposite in case of hyperthyroidism or over secretion of the hormones, when the BMR increases”, says Eileen.
The humble liver is also a very important organ where fat metabolism occurs. Ramanjit advises, “Heavy consumption of alcohol, fatty foods, especially high fat content meats, all lead to a fatty liver, leading to a slowdown in the process of fat breakdown. Non–vegetarians will do well to switch over to lean meats”. The method of meat preparation is also very important according to her. So it is thumbs up for grilled, barbecued and roasted preparations and a big NO to fried recipes. Second helpings anyone?
Know it, Beat it
- A diet for weight loss should be reduced in total kilo calories but remain adequate in all nutrients.
- The diet should contain adequate protein, all essentials vitamins and minerals, a small amount of fat, dietary fibre and enough carbohydrate to prevent ketosis.
- When behaviour modification, nutritional counseling and exercise recommendations support the meal plan, weight loss can be more successful.
- Everyone should set long term goals to pack in 30 minutes or more of moderate intensity physical activity.