Decreased immunity, hair loss, loss of appetite? Latest research: Your body may be lacking TA...

Recently, an article published in Nature emphasized the importance of the trace element zinc in the human body. Its content in the human body is second only to iron.

Zinc plays many roles in the body. It helps cells grow and divide, and participates in the metabolism of various amino acids, proteins, nucleic acids, and vitamins. At the same time, zinc can promote children's bone development, ensure the normal development of immune organs and the normal differentiation of immune cells, maintain the body's normal taste and vision, promote wound healing, and reduce the damage of heavy metals to the body.

Insufficient zinc intake can cause many problems, such as decreased immunity, endocrine disorders, hair loss, decreased intelligence, loss of appetite, etc. For growing children, zinc deficiency may also cause them to not grow tall, leading to zinc deficiency dwarfism.

Currently, there is a widespread problem of insufficient zinc intake worldwide, so it is particularly important to supplement zinc in an effective way.

PART.01

Recommended dietary intake of zinc

The Chinese Nutrition Society's dietary reference intake (DRIs) for the nutrient zinc is 12-13.5 mg/d for children, 15 mg/d for adolescents and adults, and 11.5-12.5 mg/d for pregnant women and lactating mothers.

Currently, about one-third of the world's population is zinc deficient, and zinc deficiency has become the fifth leading cause of disease and death in developing countries. Among preschool children in about half of my country's provinces, 60% have a daily zinc intake of 3 to 6 mg, which is only about half of the reference intake.

PART.02

Causes of zinc deficiency

It is now popular in China to eat more vegetables, but this may lead to zinc deficiency. Although vegetable, grain and bean foods can provide us with energy and nutrition, their zinc content is usually low and they contain some substances that hinder zinc absorption.

These substances that hinder zinc absorption are called nutritional inhibitors, including phytic acid, oxalic acid, cellulose and some heavy metals. Especially phytic acid, it is easy to combine in the body to form insoluble precipitation, so that zinc cannot be properly used by the body.

PART.03

Symptoms of zinc deficiency

Symptoms associated with zinc deficiency vary.

It can be summarized into the following aspects:

Digestive symptoms

Loss of appetite: Zinc is very important for the normal function of taste buds and digestive tract. Zinc deficiency can cause atrophy of taste bud cells and lead to loss of appetite. Babies may become picky eaters, have partial eclipses, or even have pica, such as eating dirt, paper, hair, etc.

Decreased digestive function: Zinc deficiency will affect the renewal of taste bud cells and the activity of salivary phosphatase, causing hyperplasia and incomplete keratinization of the tongue mucosa, resulting in decreased taste sensitivity and symptoms such as lack of appetite and anorexia.

Growth and development disorders

Growth retardation: Zinc is essential for the normal development of bones, muscles and reproductive system. Zinc deficiency can lead to growth retardation, short stature, and poor development of sexual organs. During adolescence, zinc deficiency may also cause delayed development of secondary sexual characteristics.

Delayed intellectual development: Zinc deficiency can impair brain DNA and protein synthesis and reduce glutamate concentration in the brain, thereby causing intellectual development delay.

Reduced immune function

Decreased immunity: Zinc is an important element for protecting the immune system. Zinc deficiency can lead to a decline in the immune system, making the body susceptible to infection and prone to repeated colds, diarrhea, pneumonia and other diseases.

Skin damage

Skin problems: Zinc is essential for skin health. Zinc deficiency can lead to dry skin, redness, scaling, hair loss, papules and other symptoms. In severe cases, enteropathic acrodermatitis, bullous dermatitis, recurrent oral ulcers, etc. Some may show irregular and scattered hair loss, with red or light-colored hair.

Eye problems

Visual impairment: Zinc deficiency may also lead to eye problems such as decreased vision and keratomelia, and may even be complicated by visual impairments such as cataracts and night blindness.

Other symptoms

Poor mental state: Zinc deficiency may manifest itself in symptoms such as listlessness, inattention, and hyperactivity.

Anemia: Zinc deficiency may also affect the synthesis of hemoglobin, leading to anemia.

PART.04

How to solve zinc deficiency

Optimize dietary combinations

Choose dietary sources rich in zinc. Common zinc-rich foods are mainly divided into the following categories:

Seafood

Shellfish: such as oysters, scallops, abalone, clams, etc. These foods are not only high in zinc, but also rich in various nutrients. They are a good choice for zinc supplementation.

Fish: such as eel, carp, black fish, Spanish mackerel, hairtail, etc., are also rich in zinc.

Shrimp and crabs: Fresh shrimp, starfish, loach, sea cucumber and other seafood products also contain high levels of zinc.

Animal meat and offal

Lean meat: such as lean pork, lean beef, lean lamb, chicken, etc. These meats are important sources of zinc.

Animal offal: such as pork liver, chicken liver, lamb liver, duck liver, goose liver, etc., are also rich in zinc and other nutrients.

Nuts

Various nuts such as walnuts, hazelnuts, pistachios, pecans, pine nuts, sunflower seeds, cashews, almonds, etc. are not only rich in zinc, but also rich in unsaturated fatty acids, protein and other beneficial ingredients.

Cereals

Some cereal foods such as millet, corn, barley, oats, germ, malt, etc. also contain a certain amount of zinc, especially the germ part of the cereal has a higher zinc content.

Vegetables

Although the zinc content in vegetables is relatively low, some vegetables such as seaweed, carrots, eggplant, soybeans, white radish, potatoes, etc. contain a certain amount of zinc.

Fruit

The zinc content in fruits is generally not high, but some fruits such as apples, fresh dates, pears, sour dates, strawberries, apricots, bananas, lemons, etc. contain relatively more zinc.

The range between normal and harmful amounts of zinc is relatively wide, and the human body has a zinc balance mechanism, so zinc overdose is generally not likely to occur.

However, if zinc deficiency symptoms occur, it may be difficult to correct with diet alone, and zinc supplements may be needed, which generally include the following types:

Inorganic zinc

Zinc sulfate: It is a commonly used zinc supplement and can be used to treat various diseases caused by zinc deficiency, such as oral ulcers, stomatitis, etc. However, patients may experience side effects such as nausea and diarrhea after taking it, so be careful not to take it on an empty stomach.

Organic zinc

Zinc gluconate preparations: such as zinc gluconate granules, zinc gluconate chewable tablets, zinc gluconate oral solution, etc. Zinc gluconate preparations are a commonly used zinc supplement in clinical practice. They are a mineral supplement that can be used to treat malnutrition, anorexia, pica, oral ulcers, growth retardation in children, etc. caused by zinc deficiency, and can also supplement the zinc element needed by the body.

Licorice zinc preparations: Commonly used are licorice zinc capsules and licorice zinc granules. Licorice zinc preparations are a zinc supplement that can be used to treat anorexia, pica, poor growth and development in children caused by zinc deficiency. They are more suitable for patients with zinc deficiency.

Lysine and zinc gluconate preparations: such as lysine zinc gluconate granules and lysine zinc gluconate tablets. This is a compound preparation composed of lysine and zinc gluconate, which also contains auxiliary sucrose and tastes sweet. It can prevent diseases caused by lysine and zinc deficiency in children and adolescents.

Zinc complex preparations

Calcium, iron and zinc oral solution: This type of oral solution not only contains zinc, but also other minerals such as calcium and iron. It is suitable for people who need multiple mineral supplements.

Other zinc preparations

Zinc citrate: This is also a common form of zinc supplement that is easily absorbed.

Yeast zinc: A zinc preparation produced using yeast fermentation technology with high bioavailability and little gastrointestinal irritation.

Protein zinc: A zinc preparation formed by combining zinc with protein, which is easily absorbed and utilized by the human body.

However, you should choose the right product based on your personal situation (such as age, gender, health status, etc.) and doctor's advice. When taking zinc supplements, you should follow the dosage and method specified in the instructions or recommended by your doctor to avoid excessive intake. At the same time, zinc supplements are best taken after meals to reduce irritation to the gastrointestinal tract.

Of course, maintaining a healthy lifestyle is not just about focusing on the intake of a certain nutrient, but also requires comprehensive consideration of diet, exercise, rest and other aspects.

References

Wang Zhaomin, Zhao Tianyao, Xue Wentong, Research progress of biofortified zinc-rich foods, Food Industry 43(07)(2022) 218-222.

Chen Xiaohui, Study on the effect of zinc deficiency on intestinal flora and its metabolites in school-age children, 2023.

Author: Zhao Xu

Biology and Medicine, College of Food Science, Northeast Agricultural University

Editor: Dong Xiaoxian

Reviewer: Liu Kun and Li Peiyuan