Nutrition

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Questions Received:

  1. Why does spicy "hot" food cause the same physical reactions as heat, for example: sweating? (Not done yet - Digestive System)

  2. What is the recommended calorie intake per day for a woman aged 19, 170cm tall and slightly over weight?

  3. How many calories and fat grams should a man consume if he's 5'11" weighs 160 pounds and runs 7 miles a day (in one hour)?

  4. What source of information can I go to to find out more on catabolic foods? And are they a healthy alternative to regular diets?

  5. I am 46 year old female. I weigh 245 lbs. Finally I am ready to diet the proper way and exercise. How many calories a day should I intake to lose weight? And more importantly, what percent should be from carbs, fat, and protein etc?

  6. Why are vitamins and minerals important to the body?

  7. Name of vitamins that increase metabolism.

  8. I have a 20 mo. old daughter who continually has problems with her bm's (bowel movements). Nothing has seemed to help. Is there anything we can do to identify a serious or not so serious problem?

  9. What is the latest research re protein intake in alcoholic liver disease when encephalopathy is suspected?

  10. How many grams of fat is 132 calories? Can I live on 132 calories a day? I am 22 yrs, weigh 11 stones and am 5 foot 2.

  11. How many of grams of fat are men and women allowed each day?

  12. How many Calories are in a pound?

Responses:


What is the recommended calorie intake per day for a woman aged 19, 170cm tall and slightly over weight?

12th March 1999

We were unable to match the criteria exactly but the following figure may be of help: females aged between 19 and 22, weighing 55 kg and with a height of 163cm, require 2100 kcals per day (Deters, 1992). The person you have specified is 7 cms taller, and this might increase the calorie requirements slightly. Of course, the number of calories required is linked to the levels of activity during the day, so somebody who is physically very active will require a greater intake, while someone who is more sedentary will require less. For example, when we are sleeping we require less than 100 calories per hour, while running consumes more than 500 calories per hour. To reach and maintain a particular bodyweight it is necessary to balance calorie intake with calorie use by the body. Calorie intake is only one aspect of what we eat - it is important also to ensure that we have a nutritious and varied diet.

Reference


How many calories and fat grams should a man consume if he's 5'11" weighs 160 pounds and runs 7 miles a day (in one hour)?

26th March 1999

The recommended daily caloric allowance for 18-35 year-old men differs from one country to another (Committee on International Dietary allowances, 1975):

Australia 2800 kcal
India 2400 kcal
Japan 2500 kcal
UK 2700 kcal
USA 2800 kcal

The different recommendations reflect differences in body build and like all broad generalisations require adaptation to particular cases. In your case, the hour of vigorous running each day will presumably increase your energy requirements somewhat. A 70 kg person running at 5.3 miles per hour has an energy expenditure of 570 Kcal per hour. You are running 7 miles in a 1-hour session and are a couple of kilograms heavier and so will be using approximately 600-650 Kcalories when exercising. Some exercise calories are allowed for in the daily recommendations already, so you would only need to add approximately 300 kcalories to the recommended allowance to cover the energy requirements of your exercise programme. In practice you will know that your diet is appropriate when your weight remains relatively stable, unless of course you are actively trying to modify your weight. With regard to the fat content of your diet, the current recommendation is that at most only 30% of your calories should be derived from dietary fat, less if possible. Remember that fatty foods are rich energy stores, providing 900 kcals per 100 grams compared with the 400 kcal per 100 grams of carbohydrate or protein, so that weight for weight a fatty food contains over twice as many calories as the other food categories. So, if your energy requirement is 3000 kcals per day, only up to 900 of those should come from dietary fat and that means about 100 grams of fatty foods.

Reference


What source of information can I go to to find out more on catabolic foods? And are they a healthy alternative to regular diets?

9th April 1999

For a historical background to the concept and a review of catabolic foods, visit www.rarebooks.net/beck/cataboli.htm

The Catabolic Diet was created by Dr. Victor Lindlahr, a Chicago-based physician who began discussing dietary matters on the radio from 1929 onwards. He developed a diet which was based on foods that he claimed required more calories to digest than they contained. These catabolic foods included certain fruits, vegetables, fish, and some other lean meats.

The body has to use energy to chew, swallow, digest, absorb, and distribute nutrients. Of course, since most foods contain more calories than are required for their digestion, the body has a net calorie gain. However, it is proposed that catabolic foods, which are all inherently low in calories and difficult to digest, would constitute a net energy loss to the body and therefore help in weight loss.

A broad range of natural foods is included in the proposed list of catabolic foods, and they could provide the basis of a healthy and nutritious diet.

Although it is clear that some foods are more difficult to digest than others, I have not yet been able to find a scientific study of the claims being made for catabolic foods. Many of the non-scientific accounts tend to emphasise enthusiasm at the expense of rigour. If you wish to find more sources of information, a search made on AltaVista using ‘catabolic food’ as the keywords will bring up several websites.


I am 46 year old female. I weigh 245 lbs. Finally I am ready to diet the proper way and exercise. How many calories a day should I intake to lose weight? And more importantly, what percent should be from carbs, fat, and protein etc?

8th April 1999

You have made a difficult decision but undoubtedly the correct decision with regard to your health and wellbeing. Although there are many schemes and techniques that promise rapid weight-loss, the best approach is to aim for a gradual and sustainable reduction in weight. For that to occur, your intake of food, and more specifically calories, needs to be slightly less than the amount of energy that you use. And the amount of energy that you use day by day needs to be increased. So, if you are able to eat less and exercise more, your weight will begin to reduce.

Now, this is very easy to say, but so very difficult to achieve. In a modern society we are under considerable pressure to eat more than we need, and to exercise less than is good for us. There is an abundance of appetising, easily assimilated, energy-rich, low-fibre, processed food attractively packaged and in a wide range of varieties. We are bombarded with food advertising via the media, and many of our social activities revolve around food. Since we have a built-in drive to find and enjoy food, it is not surprising that we are finding it increasingly difficult to keep a balance between food intake and bodily requirements. At the same time, we tend to spend more time in front of the television and sitting in the car, so that we are actually using less calories than people a generation ago. Add to that the stresses of modern living, and weight-control becomes an increasing problem.

With regard to how many calories (kilocalories) you should aim to have per day, remember that most recommendations for women who wish to maintain their normal weight lie in the range of 2000 to 2200 calories per day. In your case, since you want to begin by losing weight, the calorie content to aim for could well be lower than this. However, it has to be said that suddenly going onto a 'crash diet' of say 1500 calories a day is rarely successful in the long-term: there may be a short-term loss of weight, but many dieters simply cannot maintain the diet and rebound, quickly regaining any weight lost. This is because our bodies become adapted to eating in a certain way, and if we try to change this too dramatically our bodies rebel and we feel a powerful need to go back to the previous pattern of eating. So to be realistic, by all means begin to reduce your food intake, and particularly the proportion of rich and processed foods in your diet, but don't punish yourself to the point where you feel constantly hungry and can think of nothing but food. That will only cause you to give up.

The bulk of your calories - about 55% - should come from carbohydrates such as potatoes, pasta, rice and vegetables. Protein should constitute about 10 to 11% of your caloric intake (about 55 grams per day), and fats no more than 30%. Remember though that fats contain more calories weight-for-weight than either carbohydrates or proteins: 900 kcals compared with 400 kcals. This means that in terms of weight, fats should make up only about 13 or 14% of our diet. After carbohydrates, proteins, and fats, the remainder of the diet is made up of minerals, vitamins, and indigestible fibre.

If you decide to reduce your calorie intake significantly, make sure that you still maintain a nutritious diet. Reduce the amount of processed foods that you have - they tend to be rich in fats, salt, and sugar because the manufacturers know that we enjoy eating them - and substitute simpler, more nutritious home-made foods such as rice, pasta and vegetables. It is not really helpful to agonise over calorie content to the point where every meal becomes a calculation - that simply reinforces an obsessive interest in food. Better to ensure that you are eating in a moderate and balanced way to maintain your health.

Exercise will probably be the key. This does not mean suddenly taking up jogging, aerobics, or weight-training, since again the transition would be too extreme and it would be unlikely that you would be able to sustain them for long before giving up. It would also be medically unwise to begin a heavy exercise programme after having a sedentary lifestyle. At first, make small adjustments in your level of activity. If you are sitting down, make sure you get up every few minutes and move around. One way to achieve this is to hide the remote control for the TV. Instead of driving to the local shop, decide to walk. Where there is a choice between a lift (elevator) and stairs, take the stairs. If you have a choice between sitting and standing, remain standing. Small changes in energy use like these can help to swing the balance away from gaining weight towards a return to a more comfortable weight. Later, when you feel more capable, you may wish to take up a low-impact form of exercise such as swimming or cycling to increase your level of exercise and fitness, but you will know when you are ready to try this.

Finally, try to spend less time in environments where food is paramount - the kitchen, the food sections of supermarkets, restaurants, for example - and more time in environments where you can apply some of your energy to other interests. So when you have recreational time, rather than invite friends for a meal suggest you meet them instead at an art gallery or museum, or share a walk in the park or in the countryside.


Why are vitamins and minerals important to the body?

20th April 1999

Vitamins and minerals make an important contribution to health. Most of our knowledge concerning the importance of these has arisen from observations made when such substances have been either absent, or, deficient from the diet. The importance of vitamin C for example was first realised when sailors on long voyages began to develop haemorrhages under the skin, gum disease, loose teeth, bleeding from tooth sockets and dry scaly skin. Adding citrus fruits to their diet brought rapid relief from their suffering.

Key Vitamins

B vitamins - this is a complex group of water soluble vitamins:

Key Minerals

Mineral salts make a vital contribution to cellular homeostasis. Again, the extent to which such substances are important has often been learnt through the effects expressed when deficiencies occur.


Name of vitamins that increase metabolism

6th May 1999

It depends on what is meant by "increased metabolism". Many vitamins are coenzymes and are involved in metabolic reactions. Some of these reactions can be anabolic i.e. building up compounds and some can be catabolic i.e. breaking down biochemical compounds. Members of the vitamin B group such as riboflavin and nicotinamide are required for the synthesis of their respective coenzymes, FMN (flavin mononucleotide) and NAD (nicotinamide adenine dinucleotide) which are involved in many biochemical reactions. Vitamin C is involved in many biosynthetic pathways including collagen synthesis, formation of the neurotransmitter noradrenaline, hydroxylations involved in steroid syntheses and indirectly (via its effect on folic acid) on DNA synthesis. Conversely, vitamin E is an antioxidant and thus acts to reduce metabolic reactions i.e. oxidation from taking place, especially peroxidation reactions involving fats and vitamin A.

In summary those vitamins which are involved in metabolism mainly belong to the B group of vitamins which may act as coenzymes acting on biochemical pathways as well as vitamin C. However their effects are variable and metabolism may be "decreased" as well as "increased".

Our thanks to Geryk John, Lecturer in Pharmacology and Biochemistry, for providing this answer.


I have a 20 mo. old daughter who continually has problems with her bm's (bowel movements). She will remain constipated for two or three days and then when she does succeed, her feces are very hard and she uses all of her energy to expel the matter. We have changed up her diet and tried different juices, and veggies to try and help aid her digestion, but the problem persists. Due to advice from a nurse at our PCP's office we did the aforementioned things.

Nothing has seemed to help. Is there anything we can do to identify a serious or not so serious problem? It almost always takes a supository to get her to have a bm, and it is always way too big for her little body to pass. What can we do? Can you also direct me to a possible website that may help my wife and I figure out what to do next.

9th November 1999

It will be worthwhile to review the fluid intake of your little daughter as the picture tends to suggest that your baby may be underhydrated. Try to make an accurate assessment of your baby's current fluid intake, and check this out with the nurse who has been providing advice. "Different juices" have been tried but have these been adequately diluted?

We acknowledge the help of Maggie Doman, Senior Lecturer in Paediatric Nursing, University of Plymouth with this answer.


What is the latest research re protein intake in alcoholic liver disease when encephalopathy is suspected?

29th January 2000

Hepatic encephalopathy is a neuropsychiatric syndrome occurring in patients with acute or chronic liver disease. Such patients generally have moderate or severe malnutrition, including protein malnutrition. The precise pathophysiology of hepatic encephalopathy may differ from one patient to another, although high ammonia levels in the blood and the production of neurotransmitter-like substances in the gut have been implicated (Van Thiel et al, 1994). There are several treatments for this condition, including dietary changes, antibiotic therapy, and administration of non-digestible disaccharides.

There is still discussion about the best way to modify protein metabolism in hepatic encephalopathy. Some have reported that a reduction in protein intake is an effective treatment (Van Thiel et al, 1994), while others have found that a higher protein intake is preferable (Zavaglia et al, 1992; Morgan et al, 1995). Several clinical studies have shown that vegetable proteins are tolerated better than animal proteins (Zavaglia et al, 1992; Bianchi et al, 1993; Haycroft, 1998). It has also been proposed that the diet should be supplemented with branched-chain amino acids (Cerra et al, 1985; Rossi Fanelli et al 1986; Grungreiff, 1988; Chalasani and Gitlin, 1996), although not all studies support this (Calvey, Davis, and Williams, 1985).

The emerging consensus among dietitians working in liver transplant centres is that most patients with encephalopathy should be prescribed full calculated protein requirements, although protein restrictions are usually indicated for patients with chronic liver disease where intermittent or persistent encephalopathy becomes a quality of life issue. Overall, the main proposal is that it may be better for a patient to have mild encephalopathy but be nutritionally well (Johnson, 1998).

References


How many grams of fat is 132 calories? Can I live on 132 calories a day? I am 22 yrs, weigh 11 stones and am 5 foot 2.

16th June 2000

When we discuss nutrition, we tend to use the kilocalorie as the unit. This is equal to 1000 calories. Another way of writing kilocalorie is to put Calorie, with a capital C. We assume that you are thinking about 132 Calories? Bearing in mind that one gram of fat provides about 9 Calories of energy, then 132 Calories is provided by 14.7 grams of fat. No, you would not be able to live for long on only 132 Calories per day - the recommended daily intake for someone of your age would be closer to 2000 Calories, depending on your level of activity.


How many of grams of fat are men and women allowed each day?

16th June 2000

It is generally recommended that fat should constitute 30% of our diet or less. Unfortunately, in many countries the average level is closer to 40%, and the high proportion of fat in our food is one of the risk factors for cardiovascular disease. The recommendations for daily energy intake differ somewhat from country to country, and there are of course differences between people with regard to personal requirements, so this will affect the recommended amount of fat in the diet. Here are some examples, though, for young adults:

Country Recommended Daily Calories 30% Fat (Grams)
UK women: 2200
men: 2700
660
810
73
90
India women: 1900
men: 2400
570
720
63
80
USA women: 2000
men: 2800
600
840
67
93
Australia women: 2000
men: 2800
600
840
67
93

Remember that saturated fats should not account for more than about 10% of the total fat intake.


How many Calories are in a pound?

7th July 2000

It will depend on which substance - if it is a pound (454 grams) of carbohydrate or protein, then the energy content will be approximately 1816 Calories, since each gram can be metabolised to provide about 4 Calories. If it is fat, then the energy content is approximately 4086 Calories (about 9 Calories per gram).

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