Time to eat – Facts you must know

Time to eat – Facts you must know   

 - Prof. Dr. Shriram Savrikar

                                                                     M.D. (Ayu), Ph.D.

Feeding and fasting are aligned with the day and night cycle in a rhythm, known as circadian rhythm. A central oscillator, a body clock, located in the brain, generates daily rhythms of activity- rest and feeding-fasting. Availability of artificial light has changed the life style. Late working hours, night eating, frequent eating and binge eating have caused significant disruption of physiological rhythms of the body, giving rise to multiple metabolic disorders, like obesity. Feeding time guidelines advocated by Ayurveda still prove useful in these changed life styles.  

Popular fasting schedules:

Different feeding and fasting schedules like Continuous Energy Restriction (CER) and Intermittent Energy Restriction (IER) composed of 1. Intermittent Fasting (IMF) and 2. Time Restricted Feeding (TRF) are advised by modern day dieticians to treat obesity. Ad libitum eating (unlimited food), also known as binge eating, in feeding times, spaced with as long as 18 hours fasting periods, is advocated widely in all these schedules. None of these methods take into consideration the digestive status and potential of the individual, which varies widely from person to person. Ayurveda is way ahead in this respect.

Eating wholesome, eating less:Feeding and fasting practices advocated by Ayurveda are principally based on individual specific status of digestive functioning, automatically fulfilling the caloric and nutritive requirements. The basic principle “Hita bhuk, Mita bhuk” meaning eat wholesome and eat less, encompasses all aspects of nutritional requirements. ‘Hita bhuk’, the wholesome eating, covers qualitative nutrition. While, ‘Mita bhuk’ eating less, deals with caloric requirements. Both these factors also take care of digestive status of the individual.   “Hita bhuk, Mita bhuk” principle apart, fasting, known as Langhana in Ayurveda is used only as a therapeutic measure. The principle of eating wholesome and eating less, is simple to understand and easy to apply. It doesn’t require any consultancy from dietician or a doctor. This article will deal only with ‘Mita bhuk’ eating less related to the quantity and time of food consumption. 

 Eating times:The base line to select eating time is to eat only if earlier consumed food is completely digested and you are really hungry. If not hungry don’t eat anything, even if it is your daily time of eating. Eating over undigested food, still lying in your stomach, is the major cause of illness. How do you recognize that you are really hungry? This is not much difficult. Getting hunger pains, feeling weak, emaciated, losing interest in ongoing work, loss of energy and vigour, diminishing or blurring of vision and deepening of voice, finding difficulty in speaking, malaise and lassitude; these are all signs of true hunger. 

Fulfilling the hunger need, specific meal times are prescribed in Ayurveda. The meals are to be taken two times a day - 4 hours past sunrise around 10 AM and 4 hours past sunset around 10 PM. According to some experts evening meal needs to be taken 3 hrs past sunset i.e. around 9 PM. The evening meal should be small in quantity and light to digest, so that it gets digested before going to bed.

Once a day eaters: For few people eating only once in a day, known as ‘Ekashani’ or ‘Ekabhukta’; different meal times are recommended considering seasonal changes in the length of days and nights. When nights are longer than the day in winter and fall, the meal should be taken early in the morning, three hours past sunrise between 9AM to 9-45 AM. When days are longer than the nights in summer and monsoon, meal is taken one and half hour past mid-noon i.e. at 13-30 hrs. The meals in this season should be liquid predominant, oily and sweet. In autumn and spring when days and nights are equal, the meal should be taken at mid-noon i.e. at 12-00 hrs.

Eating between the two meals: Apart from the two meals described above, the body needs to be fed at some intervals during the day. The basic rule for such feeding is: not to eat anything within three hours of each feed and not to fast beyond 6 hours during the day. However, every time something is eaten, ensure that the food consumed on earlier occasion is completely digested. Heavy foods like foods made of grain flours are prohibited in these feeding times. These schedules are not much different from the schedules of eating followed in current times. However, the only difference appears to be in the quality and quantity of food consumed on each occasion.

Quantity of food: Quantity of food is always considered in terms of calories in modern dietetics. However, the quantity of food requirement, not only differs from person to person but also differs in one person, at different times. The principle is to take as much food as one is able to digest. Never exceed the quantity of food above the digestive capacity. Grossly dividing the stomach into four parts, 2 parts need to be filled with solids, one part with liquids and one part to be left empty. Irrespective of consistency, heavy food should be consumed to half of one’s satisfaction and light to digest food is consumed little below the satisfaction. On an average, the quantity of consumed food should be such that the person should be at ease to perform all his activities smoothly and move around comfortably. There should not be any pain or tightness in lateral or posterior part of abdomen.

Sequence of eating during meals: The quantity of food as a whole and quantity per food ingredient, also needs to be considered. It is necessary that the meal contains food ingredients of all tastes.  During eating, the food ingredients tasting sweet should be consumed first, followed by sour and salty, thereafter other foods. If fruits are part of the diet, they need to be eaten first, followed by liquids and then solids. The food should neither be excessively liquid nor excessively dry in nature.

Heavy and light food: Food preparations made of grain flours like bread, Roti, Chapati, Porridge, Laddu, Samsosa, Kachori; are heavy to digest, whereas cooked whole grain food like rice and khichari are light.  In legumes, Mung daal (Green gram) is light to digest, but its large quantities are heavy. Whereas Urada daal (black gram) is heavy even in small quantities.

Water and food: Water is an important part of every meal. It needs to be consumed frequently during the meals. Drinking of water, only after completing the meals is detrimental to health ‘Bhojanante Visham Vari’. Water consumed prior to taking meals reduces digestion and produces emaciation. Water consumed during the meals stimulates digestion, and water consumed at the end of meals promotes obesity.

Post meal activities: Lying down on the bed immediately following meals is strictly prohibited. A small 100 step stroll, known as ‘Shatapadi’ after meals proves beneficial. No vigorous physical activity should be undertaken within 3 hours of taking meals.

Ayurvedic Feeding schedules vis a vis Early Time Restricted Feeding (eTRF): A comparison of Ayurvedic feeding schedules with early Time Restricted Feeding, based on a representative study is submitted below for those who are interested. 

Upshot of Ayurvedic feeding schedules:

1.     Two times meals spaced between 9 AM to 9 PM.

2.     Mid-day feed not a meal, placed within 3 to 6 hours of either meal

3.     Ensuring minimum 12 hours overnight fasting.

4.     One fourth part of stomach to be kept empty on each occasion.

5.     Nothing should be eaten over undigested food, left over in the stomach.

6.     Evening meal as light and as less, to enable complete digestion before going to bed.

Salient features of Early Time Restricted Feeding (eTRF):

1.     Restricts feeding time window, not the quantity of food.

2.     Uniform quantity of food within 8 hours, promoting binge eating.

3.     Fasting between 8 AM to 2 PM with 18 hrs.

4.     eTRF Mean glucose levels similar to 12 hour fasting during the day but lower during sleep, leading to reduction in mean 24 hr glucose levels and glycemic excursions.

5.     Significantly high glucose, high insulin and high HOMA-IR levels observed in the night in eTRF, which is not a good sign.

6.     Not much difference observed in morning insulin and HOMA levels.

7.     Total cholesterol levels in eTRF are observed increased. HDL high in 12 hr fasting in night and in eTRF in day. eTRF is also found to reduce oxidative stress in the night.

It clearly shows that the advantage of eTRF is restricted to the night. The shortfall of this study as compared to Ayurvedic feeding schedules, is uncontrolled quantity of food in 18 hours and 12 hours fasting groups, promoting binge eating, which is the basic cause of all metabolic disorders.  

Binge eating: Ingestion of entire day’s calories in one or two feeds is the major shortfall in eTRF and similar feeding schedules. Studies indicate binge eating causes fasting hyperglycemia, fasting hyperinsulinemia and modulation of diurnal rhythm of leptin.  Reports on effects of one time, six to nine time and three time eating schedules indicate three time eating schedule beneficial above all. Striking increase in urinary dopamine excretion following binge eating is observed in one study. It is associated with insulin resistance and hypertension.  

To conclude an English proverb “Breakfast like a king, lunch like a warrior and dinner like a beggar” appears completely in line with what Ayurveda advocates. The only issue is few people follow it. So follow Ayurveda and set your eating time table to enjoy a healthy life.

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