Our Longevity Diet

A recent study supports the idea that intermittent fasting can be a useful technique for weight loss, even among obese subjects. Long-term results, of course, would require a commitment to lifestyle that incorporates a fasting regime, but this short-term study is suggestive of the potential.

The Study

Doctoral students Surabhi Bhutani and Monica Klempel, and clinical coordinator in physical therapy Emily Church, conducted a 10 week study on 16 clinically obese people. The subjects all weighed in excess of 210 pounds and had body mass indexes (BMI) between 30 and 39.9. There were 12 women and 4 men in the study, aged 35 to 65. None was diabetic, and none were taking weight-loss medication, nor lipid or glucose lowering medicines.

The weights of the study subjects had been stable for the three months preceding the study. For the first two weeks of the trial they ate normally and maintained their normal activity levels, during which time their weight, blood pressure, heart rate and blood chemistry were measured.

For four weeks the subjects were allowed to eat normally one day, then on the fasting days they were fed a single meal at lunch time with about 20 to 25 percent of their normal daily energy needs. For the last four weeks of the study subjects were allowed to set their own meal size and composition, as well as schedule.

Subjects lost from 10 to 30 pounds each, and their blood pressure and heart rate were lowered. Total cholesterol and circulating fat levels were also reduced.

Source

University of Illinois at Chicago; reported at http://www.medicalnewstoday.com/articles/169885.php on 5 Nov 2009

Comments

It is surprising that the results were so good for such a poorly designed study. There appears to have been no control group, and it is not exactly clear how much weight loss came during the semi-supervised ‘fast’ days, and how much from the self-monitored weeks that followed. The researchers took the ‘alternate day’ part of alternate day fasting too literally, and designed a diet that effectively had two short fasts interrupted by a meal on ‘fasting’ days, alternating with normal eating days. If they had used 24 hour fasting periods alternating with 24 hour eating periods, it would have been much more comfortable (and sustainable) for the subjects. This study does suggest that intermittent fasting is an effective weight-loss technique, however, and deserves closer attention from researchers and nutritionists.

With intermittent fasting, we often emphasize that when you eat is more important than how much you eat, when it comes to losing weight and maintaining good health. This is no excuse to pig-out of course, but eating to satiety is fine within an alternate day fasting regime. But is that enough for a healthy diet?

Of course not. What you eat is very important to your overall health, regardless of the schedule or quantity of food you consume. Eat nothing but junk food, and no amount of fasting or calorie restriction will counteract the ill effects of unhealthy eating.

A Nutty Example

A recent study examined the effect of daily consumption of pistachios on gamma-tocopherol serum levels. Gamma-tocopherol is a form of vitamin E which has been shown to reduce the risk of lung and prostate cancers, and perhaps other forms of cancer. Other studies have shown pistachios to have a beneficial effect on heart health by lowering LDL cholesterol, as well.

In this study, half the participants added about two ounces of pistachios to their daily diet, for a period of four weeks, while the other half continued their normal diets. Cholesterol-adjusted serum gamma-tocopherol was significantly higher at the end of the period for those eating pistachios, compared to their own pre-diet baseline, while the control group showed no significant change.

Good Food

That is just one of the hundreds of studies we see each year that show how good foods have beneficial affects on our bodies. It’s not just pistachios — most nuts are healthful eating. Fresh vegetables are great for you too.

Meat has a bad reputation among many health-conscious folk today, but really, there is no other food that has as great a variety of beneficial nutrients. All meat has fat in it, and too much fat — especially the saturated fats common in meat — can cause problems. But those problems can be avoided.

If called upon to do so, your body will turn those fats into energy. The amount of meat in your diet should be in direct correlation with the amount of vigorous exercise you get. A healthy diet for one person is not always a healthy diet for someone with a different lifestyle.

Likewise, fruit can be packed with good minerals and vitamins, but eating too much fruit will be unhealthy for someone whose lifestyle if very sedentary, because most fruits also contain high sugar levels.

Balance

Intermittent fasting can help you lose weight, and also produces beneficial health effects that promote longevity. But a healthy diet must be part of your lifestyle, or all those beneficial effects will be countered by more powerful ill effects.

You need a diet balanced with good healthful fat, fiber, sugar/carbohydrates, vitamins and minerals in the right approximate proportions for your lifestyle. A ‘fat free’ diet would kill you if you could achieve it. Each of these things are a necessary part of a healthy diet — the quantities and proportions varying depending on how much energy you expend in your daily life.

Variety is not just the spice of life — it is the easiest path to a healthy diet. Eat as many different fresh and healthful foods as you can, with plenty of clean water. Your body will then be able to sort out what is best for you, and dispose of the rest. You can usually trust your appetite to lead you to the foods your body needs most — being aware that sugar and fats tend to be craved far in excess of their actual merit.

Strike the balance that is right for you — you will know by how it makes you feel when you are doing the right thing. There is no need for exact measurements of portions and strict rationing of certain foods. Just reduce the fat and sugars if you are sedentary, and eat a great variety of healthful foods. Drink plenty of clean water. Voila — you have a healthy diet.