How to eat a low-carb, low-fat diet, many people get their basic concepts wrong...
A low-fat diet does not mean not eating meat. In a low-fat diet, high-fat foods such as butter, offal, and fried foods should be avoided; the fat-reduction effect of a low-carb diet is better than low-energy high-carb water in the short term Compound low-fat diet, and the long-term effect is similar to low-energy, high-carbohydrate, low-fat diet.
With the improvement of living standards, more and more people begin to pay attention to the way of eating, that is, choosing a healthier diet according to their own needs. Among them, low-fat diet and low-carbon diet are very popular. In a low-fat diet, what to eat has become the focus of attention. When it comes to fat, people often think of all kinds of meat products, thinking that meat food is the culprit leading to excessive fat intake; when it comes to low-carbon diet, it has become a magic weapon for many people who lose weight, but by reducing their diet Can the carbohydrates in carbs achieve the goal of weight loss? A recent study showed that the effect may not be as perfect as imagined.
Low-fat diet is equivalent to not eating meat? What you really should avoid are high-fat foods
As we all know, many clinical diseases require patients to take a low-fat diet. Most of us know that meat has a high fat content. So, is a low-fat diet equivalent to not eating meat?
"A low-fat diet refers to a diet in which dietary fat accounts for less than 30% of the total calories of the diet or the total daily fat intake is less than 50 grams." Tian Ying, deputy chief physician of the Heart Center of Beijing Chaoyang Hospital, Capital Medical University, said in daily life What we should really avoid or reduce is the intake of high-fat foods, such as butter, offal, fried foods, and preserved foods.
Experts said that low-fat diets are not recommended to eat fatty meat, animal offal, poultry meat skin, fish roe, shrimp roe, crab roe, etc. In fact, fish meat, lean meat of poultry and livestock, etc. are not high in fat, especially fish meat, not only does not contain much fat, but the fat contained in fish meat is conducive to the protection of cardiovascular and cerebrovascular, maintenance of the retina and improvement of vision. Fatty acids, therefore, it is recommended to eat fish, especially some deep-sea fish, such as salmon, tuna, mackerel, eel, small yellow croaker, hairtail, etc.
In fact, fat in the human body is a good energy storage substance in cells, which can provide heat energy, protect internal organs and maintain body temperature. In addition, fat can also assist in the absorption of fat-soluble vitamins and participate in various aspects of the body's metabolic activities.
From this point of view, a low-fat diet is not the same as not eating meat, so how can we have a healthy low-fat diet?
Tian Ying pointed out that in our daily life, we can divide low-fat diets into three levels: a lightly restricted diet refers to a daily total fat intake of not more than 50 grams; a moderately restricted diet refers to a daily The total fat intake does not exceed 40 grams; a severely restricted fat diet means that the total daily fat intake does not exceed 20 grams.
"You can formulate appropriate recipes based on the recommendations of clinicians and health nutritionists, develop good eating habits, and choose foods with less fat. Only when the fat content is reasonable can you ensure the body’s nutritional needs and provide reasonable nutrition. Support. You can choose different levels according to different needs and find your own recipes." Tian Ying emphasized.
Is low-carbon and fat-reducing diet healthier? The effect is controversial, the latest research shows that it may affect cardiovascular health
In addition to low-fat diets, low-carbohydrate diets and quit-carbohydrate diets have become a direction that many people yearn for in eating habits. Some people think that a low-carb and abstinent diet is an effective way to lose weight and is healthier than dieting.
Low-carb diet refers to a low-carbohydrate diet, that is, strictly limit the intake of carbohydrates in the diet and increase the intake of protein and fat. It was first proposed by Atkins, an American, in "Doctor Atkins's New Diet Revolution" in 1972.
At present, the effect of low-carbon diet is still controversial in the medical field. Proponents believe that low-carb diets can reduce body weight (about 10% on average) and blood cholesterol levels (about 5% on average) to a certain extent, and reduce the risk of heart disease, but it is uncertain whether it will be effective in the long term. Opponents believe that few people can stick to a low-carbon diet for a long time. The study found that only 1% of people can stick to it for a long time, an average of 19 months. In addition, low-carb dieters eat less carbohydrates, and eat more protein and fat. This runs counter to the health concepts of the medical and nutrition circles. It is not suitable for patients with coronary heart disease, gout, and kidney disease.
Recently, after a comprehensive review of existing evidence, the National Lipid Association of the United States issued a consensus that low-carb diets have no advantage in weight loss and cardiovascular health effects, but are dangerous.
In this consensus, low-carbon diet is defined as 10%-25% of total daily energy from carbohydrates, that is, 50g-130g of carbohydrates consumed per day; very low-carbon diet is defined as the total daily energy from carbohydrates. The ratio is less than 10%, that is, less than 50 grams of carbohydrates are consumed per day. The consensus pointed out that people who follow low-carbon and very-low-carbon diets have reduced appetite and hunger, which seems to increase the body's energy expenditure, but the specific mechanism is unknown. This may be related to changes in catecholamine and thyroid hormone levels.
Consensus states that the short-term (≤6 months) effect of low-carb and very low-carb diets for weight loss is better than that of low-energy, high-carbohydrate and low-fat diets, while the long-term (>6 months) effect is similar to low-energy and high-carb diets. The compound low-fat diet is similar. In addition, a very low-carbon diet is difficult to maintain, and compliance is poor. The consensus is that eating less is the last word to lose weight, and changing the ratio of carbohydrates, protein, and fat has no effect.
"The human body has two purposes for ingesting food: one is to consume chemical energy into heat and mechanical energy to maintain energy conservation; the other is to supply structural molecules to renew cells and catalytic reactors. To meet these two purposes, a balanced diet is the key "Song Qing, a professor at the School of Chemistry and Biological Engineering, University of Science and Technology Beijing, said in an interview with a reporter from Science and Technology Daily.
"Excessive high-energy molecules will be converted into adipose tissue to cause obesity, while lack of essential fatty acids that cannot be synthesized by itself, essential amino acids and various vitamin auxiliary molecules will cause metabolic and endocrine diseases. Low-carb and low-fat diets are both for satisfying A compromise solution for strong appetite. Controlling the total amount of food intake, increasing the variety of food, and increasing the amount of exercise are shortcuts to maintaining health. As the saying goes, keeping your mouth open and opening your legs is the right way of life." Song Qing emphasized.
Further reading
"Sugar-coated cannonballs" on the road to low-carb and low-fat diets
In daily life, some seem to be high-fat foods whose fat content does not reach the high-fat standard; and some foods seem to be low in carbohydrates but are not the case. For examples like this, what else are there in life?
Nuts are a "sugar-coated cannonball" on the road to a low-fat diet. Nuts are rich in protein, unsaturated fatty acids, vitamin E, B vitamins, calcium, iron, etc., moderate intake is indeed good for health. But its fat content is relatively high, reaching about 40%-70%. Experts suggest that you must eat nuts in moderation and keep them below 10 grams per day.
In addition, we must be wary of certain "invisible fats", such as ice cream, butter cakes, snacks, fried foods, processed meats such as sausages, cured meats, luncheon meats, etc. When buying these foods, people often do not think they are high-fat food. Compared with carbohydrates and protein, fat provides higher calories. The same 100 grams of potatoes, boiled and eaten energy only 70 calories, made into French fries, the energy increased to 150.1 calories, directly more than doubled. In addition, food will produce many harmful substances during frying, some of which can cause cancer.
"Although the whole milk we often say has relatively high fat content, it is rich in aromatic substances. Eating high-fat milk is no problem for adults." Song Qing said. Generally speaking, foods with a fat content of more than 20% are considered high-fat foods, while the fat content in whole milk is usually 3.0-3.5g/100g, which is not a high-fat food. For most adults with normal weight and normal blood lipids, drinking half a catty to one catty of whole milk a day is beneficial; for people who are overweight or obese but have not yet suffered from atherosclerosis, as long as their blood lipids reach the standard, It is safe to drink half a catty of whole milk a day; for those who are overweight, obese or have obvious dyslipidemia, especially for cardiovascular and cerebrovascular patients with atherosclerosis, it is advisable to drink skimmed milk; for those who need to control calories to prevent obesity or Elderly people with dyslipidemia or weak digestion can choose low-fat milk in an appropriate amount.
Our reporter Ma Aiping