Vitamin A (Retinol)
Vitamin A is a fat-soluble vitamin that can be stored in the liver. Rich food sources include fish, liver, butter, eggs, whole milk and full-fat dairy products. About 50 of the approximately 600 carotenes found in plant foods have vitamin A activity.
These carotenoids are called provitamin A. In the liver and small intestine, enzymes convert them to vitamin A by incorporating 1 mole of water into their structures. In terms of equivalence, 6–12 mg of carotene equals 1 mg of vitamin A.
Functions of vitamin A in the body
1. Provides the eye’s adaptation to the dark and prevents night blindness.
2. Has vital importance for growth, bone development, reproduction, immune system, and health of epithelial tissues.
3. It is an antioxidant. It delays aging and reduces the risk of cancer.
4. Increases resistance to diseases and protects against cold and flu. It provides protection against infection and air pollution in the mouth, nose, throat and lungs.
Vitamin A deficiency
When the amount of retinol in the blood drops below 20 µg/dL, the stores are insufficient; When it falls below ten µg/dL, it is accepted that there is no stored vitamin A.
Since vitamin A can be stored in the liver, deficiency symptoms appear within 1-2 years in adults.
Deficiency can occur in people with malabsorption, celiac disease, gallbladder disorders, cirrhosis, chronic pancreatitis or inflammatory bowel disease, as well as in those following a restrictive diet.
Diseases in Vitamin A deficiency;
1. Night blindness (appears after about seven months in its deficiency) and xerophthalmia (appears within 3-5 months)
2. Dryness and keratinization of the skin,
3. Increase in respiratory tract infections,
4. Increase in kidney epithelial disorder and kidney stone formation,
5. Infertility,
6. Disturbances in growth and development may occur.
When vitamin A is taken in excess by the body;
Generally, taking more than ten times the daily recommended intake of vitamin A has a toxic effect. The consumption of 15 mg per day for adults and 6 mg per day for infants and children may cause poisoning symptoms.
If taken in excess;
1. Enlargement of the liver and spleen,
2. Hair loss,
3. Growth arrest,
4. Bone and muscle pain,
5. Scaling and itching on the skin,
6. Nausea and vomiting,
7. Double vision,
8. Situations such as miscarriage and birth disorders may be encountered.
As mentioned above, 6–12 mg of carotenes is equivalent to 1 mg of vitamin A.
Storage and processing conditions can reduce a food’s vitamin A content. The table below shows the conditions to which vitamin A is sensitive. Cooking can cause vitamin A losses of up to 40%.
Vitamin A is also sensitive to light and air. Storing food away from light and air is therefore important for preserving its vitamin A content.
Vitamin D (Calciferol)
Vitamin D is the collective name for about ten compounds with antirachitic activity, designated D1, D2, D3 and so on. The most important are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).
Vitamin D3 can be produced in the body, while vitamin D2 is produced artificially in the laboratory. Vitamin D2 is usually added to foods to enrich them or used as a food supplement.
Vitamin D can be produced within the body of every individual who receives sufficient sunlight and the body can provide an adequate amount to metabolism. However, individuals who cannot get enough sunlight cannot produce enough vitamin D in their bodies. In this respect, sunbathing for 15-30 minutes is extremely important for vitamin D production.
Vitamin D is fat-soluble and can be stored in the liver. Rich food sources include fish oil, egg yolk, butter, cultivated mushrooms, whole milk and full-fat dairy products.
Functions of vitamin D in the body
1. Provides the absorption of calcium and phosphorus in the digestive system,
2. Regulates the calcium level in the blood,
3. Provides parathyroid inhibition,
4. Provides gene regulation,
5. Helps cell regeneration.
Vitamin D deficiency
Vitamin D deficiency can be seen in individuals who cannot receive direct sunlight, workers who work at night, individuals with malabsorption, chronic kidney and liver disease, fast-growing children and individuals from countries with low sun exposure.
If there is not enough vitamin D in the body, calcium and phosphorus taken with the diet cannot be adequately absorbed in the digestive system. Therefore, the calcium level in the blood decreases. To complete the calcium deficiency in the blood, the calcium in the bones is dissolved and given to the blood.
As a result, children develop abnormalities in bone development and bone deformities. This condition is called rickets. In adults, it causes osteomalacia, which softens and bends the bones. Osteomalacia is common in women who have frequent pregnancies, are undernourished and do not receive enough sunlight.
When vitamin D is taken too much;
Exposure to excessive sunlight increases the risk of developing skin cancer, but it is reported that excessive vitamin D production in the body does not pose a toxic hazard.
However, if the amount of 10 times the recommended daily intake is taken continuously;
1. Hypercalcemia and hyperphosphatemia; high levels of calcium and phosphorus in the blood,
2. Hypertension,
3. Developmental delay,
4. Nausea, weakness, diarrhea, excess urine,
5. Weight loss,
6. Kidney stone formation,
7. Nausea and vomiting,
8. Fatigue and headaches can be encountered.
Cooking can cause vitamin D losses of up to 40%. Vitamin D is also sensitive to light and air or oxygen. Storing food away from light and air is therefore important for preserving its vitamin D content.
Vitamin E (Tocopherol)
Vitamin E is the common name for eight different tocopherols. Nutritionally, α, β, γ and δ – tocopherols are important.
Vitamin E is one of the fat-soluble vitamins; It can be stored in the liver and adipose tissue. It is heat resistant. However, its resistance to heat decreases in the presence of oxygen.
The most important feature of vitamin E is its strong antioxidant effect. Vegetable oils, butter and eggs are foods rich in vitamin E. Vitamin E deficiency is very rare.
Functions of vitamin E in the body
1. Prevents the oxidation of unsaturated fatty acids in the structure of the cell wall and thus ensures the integrity of the intracellular membrane,
2. Helps the nerve and muscle tissue to work regularly,
3. With its strong antioxidant properties, it helps protect the body against aging and cancer,
4. Protects blood cells against hemolysis,
5. It has functions in the formation of sperm and ovum cells.
Vitamin E deficiency
A level of vitamin E in the blood below 0.5 mg/dL is defined as vitamin E deficiency. Vitamin E deficiency is rare, except in premature infants and individuals with fat absorption disorders.
Diseases in Vitamin E deficiency;
1. Poor coordination between the nervous system and muscle movements,
2. Reflex loss,
3. Reduction in muscle mass; weakening,
4. Reproductive system problems can be seen.
When vitamin E is taken in excess to the body;
No adverse effects have been reported from consuming large amounts of vitamin E from food. However, high-dose vitamin E supplements can interfere with blood clotting and increase bleeding risk. People taking anticoagulant or antiplatelet medicines should consult their physician before taking vitamin E supplements. (NIH Office of Dietary Supplements, 2026)
After the food is cooked, losses of up to 55% can occur in vitamin E. Vitamin E is resistant to heat under normal conditions. Still, the presence of oxygen in the environment considerably reduces the resistance of vitamin E to heat.
Vitamin E is sensitive to light and air. Protecting food from light and air helps preserve its vitamin E content, as it does for many other vitamins.
Vitamin K
Vitamin K is the common name of 5 different molecules called K1 (phylloquinone), K2 (menaquinone), K3 (menadione), K4, and K5. K1 and K2 are molecules found in nature, while the other three molecules are synthetically produced in the laboratory.
Vitamin K1 is in the composition of foods. Vitamin K2 is produced by bacteria living in the intestines. While the body obtains half of its vitamin K needs from foods, the other half is obtained from vitamin K produced by the bacteria living in the intestines and absorbed from the colon.
Vitamin K is a fat-soluble vitamin stored in the liver and some other tissues. Deficiency is rare.
Functions of vitamin K in the body
1. Has an essential function in blood coagulation. It is involved in the synthesis of prothrombin.
2. Transfers electrons in respiration reactions,
3. Effective on bone health.
Vitamin K deficiency
The daily requirement of vitamin K is one µg/kg of body weight. For example, the daily need for vitamin K for an individual weighing 70 kg is 70 µg. Vitamin K deficiency can be seen in individuals with impaired fat absorption and individuals who use high amounts of antibiotics.
In its deficiency, symptoms usually appear after 1-2 weeks. In the case of surgery and injury, an increase in bleeding may occur.
Diseases in Vitamin K deficiency;
1. Problems in blood coagulation,
2. Abnormalities can be seen in the intestinal walls.
When vitamin K is taken too much in the body;
High vitamin K intake can cause prolonged clotting time, hemolytic anemia and vomiting, as well as jaundice in newborn babies.
Vitamin K is highly resistant to heat treatment and air. However, like other vitamins, it is sensitive to light.
Vitamin C (Ascorbic Acid)
Vitamin C is water-soluble. Its main food sources include rosehips, green pointed peppers, kapya peppers, parsley and citrus fruits. Rosehips contain approximately 600 mg per 100 g.
Vitamin C is very unstable to ambient conditions. Over 90% of vitamin C loss can occur with cooking. Similarly, the cutting process applied to food causes a significant loss of vitamin C.
Consuming vitamin C-rich foods without cooking or cutting them is important for vitamin C intake. Rosehips are not commonly eaten raw; they are usually consumed as tea or marmalade. As a result, the vitamin C obtained from this rich source may be less than expected.
Likewise, although potatoes and liver contain high levels of vitamin C, it is not meaningful to consider them vitamin C sources when cooking destroys almost all of it. Eating chopped green peppers in a salad provides less vitamin C than eating them without chopping.
It is recommended to consume fresh foods such as citrus fruits and peppers without cutting and chopping. Vitamin C is also highly sensitive to light, oxygen and metals.
In addition to being a natural ingredient in foods, vitamin C is added to processed foods as a food additive in the food industry. The most important reason for using vitamin C as a food additive is to protect the color.
It prevents the product from darkening and helps maintain a stable color. On food labels, it is usually listed as ascorbic acid, with the code E300, and identified as a color stabilizer.
Functions of vitamin C in the body
1. Takes part in the synthesis of collagen, which is connective tissue,
2. Helps to prevent coronary heart diseases by preventing the oxidation of intravascular cells and LDL cholesterol,
3. Protects the body against infections and bacterial toxins,
4. Effective in protecting gum health,
5. It is an important antioxidant; it reduces the risk of cancer.
Vitamin C deficiency
The recommended daily vitamin C intake for a healthy adult is 60–100 mg. Smokers are advised to obtain an additional 10 mg of vitamin C for each cigarette smoked. Stress, medication or chemical use, and illness are other factors that increase vitamin C needs.
Diseases in Vitamin C deficiency;
1. Scurvy can be seen,
2. The durability of capillaries decreases; bleeding in the gums and under the skin,
3. The healing of wounds is delayed,
4. Connective tissue formation is impaired, and the ends of the bones become particularly fragile,
5. Blood clotting time increases,
6. Teeth may be wobbly.
When vitamin C is taken too much in the body;
Excess vitamin C is excreted through urine. However, excessive vitamin C intake can cause diseases such as diarrhea and kidney stone formation. On the other hand, it has been reported that excessive intake reduces the absorption of vitamin B12.
It has been mentioned before that vitamin C is highly unstable to ambient conditions. Vitamin C suffers significant losses after cooking, cutting and canning. However, it is extremely unstable to air and light. The presence of metal ions in the environment causes the loss of vitamin C by accelerating the oxidation of vitamin C.
Vitamin B1 (Thiamine)
Vitamin B1 is popularly known as the “morale vitamin.” Because it is directly involved in carbohydrate metabolism, thiamine needs increase with high carbohydrate intake and high energy expenditure.
In general, 0.5 mg of vitamin B1 is recommended for every 1,000 calories expended. Early deficiency symptoms include loss of appetite, depression, increased sensitivity and mental fatigue.
Vitamin B1 is water-soluble and occurs in almost all animal and plant foods, although sometimes in small amounts. Sourdough bread is its richest source. Whole-wheat bread made from flour that retains the bran and germ, as well as bulgur, is also a good source of thiamine.
Functions of vitamin B1 in the body
1. Thiamine is a cofactor in the structure of 3 enzymes involved in carbohydrate metabolism (pyruvate dehydrogenase, α-ketoglutarate dehydrogenase and transketolase). Therefore, it has a direct effect on carbohydrate metabolism.
2. Supports the regular functioning of the nervous system,
3. Necessary for cardiovascular health,
4. Helps the digestive system function regularly by facilitating digestion,
5. Increases learning ability.
Vitamin B1 deficiency
The recommended daily intake for a healthy individual is approximately 1.0 mg. However, as stated before, the need increases in high carbohydrate consumption and increased energy expenditure cases.
The thiamine requirement of an individual whose daily energy consumption is 3000 calories is approximately 1.5 mg/day.
The need for thiamine increases in pregnant women, lactating women and individuals who have experienced accidents and trauma. Vitamin B1 deficiency is generally encountered in Far East countries.
Diseases in Vitamin B1 deficiency;
1. Loss of appetite, depression and mental fatigue,
2. Indigestion, severe constipation, irregular bowel movements,
3. Beriberi, which is a nervous system disease,
4. Wernicke-Korsakoff syndrome,
5. Heart failure, respiratory failure and palpitations may occur.
When vitamin B1 is taken in excess to the body;
No toxic or side effects have been reported when vitamin B1 is taken in 500 mg daily.
Vitamin B1 is highly sensitive to environmental conditions. Cooking and heat treatment cause substantial thiamine losses, but it is resistant to air and oxygen.
Vitamin B2 (Riboflavin)
Vitamin B2 is included in the structure of enzymes that have oxidation-reduction functions in the reactions occurring in the cell. It is an important vitamin in the metabolism of carbohydrates and fats, especially proteins. Riboflavin is involved in the structure of approximately 50 different enzymes in mammals.
Vitamin B2 needs increase with daily energy expenditure. In general, the recommended daily intake for a healthy person is 1.2 mg. Expressed in relation to energy needs, approximately 0.6 mg of vitamin B2 is recommended for every 1,000 calories expended.
Vitamin B2 is a water-soluble vitamin and its most important sources are sourdough bread, beef liver, eggs and cultivated mushrooms. Its deficiency is mainly seen in individuals from economically backward countries.
Functions of vitamin B2 in the body
1. Riboflavin participates in the structure of FMN (flavin mononucleotide) and FAD (flavin adenine dinucleotide) enzymes in the body. Therefore, it is extremely important in the healthy execution of energy metabolism.
2. Makes vitamin B6 active,
3. Takes part in the production of erythrocytes,
4. Takes part in the production of glycogen.
Vitamin B2 deficiency
The recommended daily intake for a healthy individual is approximately 1.2 mg. However, as stated before, the need increases in cases such as high energy expenditure. The riboflavin requirement of an individual with a daily energy consumption of 3000 calories is approximately 1.8 mg/day.
Riboflavin needs also increase during pregnancy, breastfeeding and growth. Symptoms of inadequate vitamin B2 intake generally begin to appear within three months.
Diseases in Vitamin B2 deficiency;
1. Sores on the skin, genitals, nose, mouth, lips and tongue,
2. Enlargement of the eye vessels, difficulty in seeing and burning in the eyes,
3. Disorders in the nervous system can be observed.
When vitamin B2 is taken too much in the body;
No toxic effects have been reported after taking high doses of vitamin B2.
Vitamin B2 is more resistant to environmental conditions than other vitamins. However, as a result of cooking, up to 75% of the amount of vitamin B2 in the food can be lost. Also, like other vitamins, it is sensitive to light.
Vitamin B3 (Niacin)
Niacin is the common name for nicotinic acid and nicotinamide. It is found in the structure of nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) enzymes in the body. Therefore, it has a vital function in energy production reactions.
While niacin can be found in free form in foods, tryptophan, an essential amino acid, can be converted to niacin in the liver. Approximately 60 mg of tryptophan is equivalent to 1 mg of niacin.
Consuming foods rich in vitamin B3 and high-quality protein is important for carbohydrate, fat and protein metabolism. Vitamin B3 deficiency manifests as pellagra in populations whose staple food is corn and whose protein sources are of low quality.
Vitamin B3 is water-soluble and more resistant to environmental conditions than many other vitamins. Its richest food sources include sourdough bread, liver, cultivated mushrooms and bulgur. Niacin needs increase with daily energy expenditure; in general, 6.6 mg per 1,000 calories expended is recommended.
Functions of vitamin B3 in the body
1. Plays a key role by taking part in the structure of enzymes carrying electrons in energy production reactions.
2. Necessary for acid production in the stomach,
3. Supports skin health,
4. Important for the health of the nervous system.
Vitamin B3 deficiency
The recommended daily intake of vitamin B3 for a healthy adult is 13–18 mg. Niacin needs increase as energy expenditure rises. Pregnancy and breastfeeding also increase the requirement.
Diseases in Vitamin B3 deficiency;
1. The skin becomes sensitive to light; burning and redness can be seen in the skin. In advanced cases, pellagra disease occurs; nervous system and digestive system disorders occur, wounds and lesions occur on the skin.
2. Redness of the tongue and dryness of the mouth,
3. Diarrhea, vomiting and abdominal pain,
4. In advanced cases, nervous disorders such as anxiety, insomnia and hallucinations can be seen.
When vitamin B3 is taken too much in the body;
When more than 3 grams of vitamin B3 is taken daily, side effects may occur in the body. When the amount of consumption is reduced, the side effects also disappear.
Known side effects;
1. Hot flush and skin flushing,
2. Disorders in liver functions,
3. Enlargement of the veins.
It can be said that vitamin B3 is the most resistant vitamin to environmental conditions. Possible loss occurs by cutting and washing the food.
Vitamin B5 (Pantothenic Acid)
Pantothenic acid forms part of coenzyme A (CoA), which participates in important reactions such as the Krebs cycle, fat and protein metabolism, and cholesterol production.
Vitamin B5 deficiency is very rare. If food is not taken for more than three months, it can cause symptoms of mild paralysis in the hands and feet.
Vitamin B5 deficiency can occur in people with inadequate nutrition or digestive system disorders.
Vitamin B5 is a water-soluble vitamin found in almost all animal and plant foods in greater or lesser proportion. The best sources of pantothenic acid are sourdough bread, beef and liver, eggs and cultivated mushrooms.
Functions of vitamin B5 in the body
1. Has essential roles in carbohydrate, lipid and protein metabolism.
2. Acts as a carrier in cell metabolism.
Vitamin B5 deficiency
The recommended daily intake of vitamin B5 for a healthy adult individual is approximately 6 mg.
Diseases in Vitamin B5 deficiency;
1. Weakness, nausea, vomiting,
2. Muscle cramps, nerve damage,
3. Burning feet syndrome can be seen.
When vitamin B5 is taken too much;
No toxic or side effects have been reported due to the regular intensive use of pantothenic acid.
Vitamin B6
Vitamin B6 is a common name given to pyridoxine, pyridoxal and pyridoxamine. These compounds are found in foods combined with phosphate. The most useful for metabolism is pyridoxal phosphate. The deficiency of this vitamin is rare.
Vitamin B6 is involved in protein metabolism in the body. It is also found with protein in foods. Therefore, as the amount of protein in the food increases, the amount of vitamin B6 it contains also increases.
Vitamin B6 is water-soluble. Its richest sources include meat and offal, eggs, cereal products, legumes and sourdough bread.
Functions of vitamin B6 in the body
1. It forms part of enzymes involved in amino acid decarboxylation and deamination reactions,
2. Involved in the synthesis of hemoglobin,
3. Takes part in some reactions in fat and carbohydrate metabolism,
4. Supports the regular functioning of the immune system.
Vitamin B6 deficiency
The recommended daily intake of vitamin B6 for a healthy adult individual is 1.0 – 1.6 mg. The need for vitamin B6 in the body also increases in a protein-based diet and cases of stress.
Diseases in Vitamin B6 deficiency;
1. Anemia and convulsions,
2. Growth retardation,
3. Digestive system disorder and kidney stone formation,
4. Restlessness and neurological disorders can be seen.
When vitamin B6 is taken too much in the body;
When more than 500 mg of vitamin B6 is taken daily, side effects may occur in the body.
Known side effects;
1. Sensory disorders,
2. Disorders in the nervous system.
Vitamin B6 is relatively unstable to light and heat treatment. It can lose between 40% – 80% in canned food production; it can lose between 40% and 60% in the freeze-preservation process.
Vitamin B12 (Cobalamin)
Vitamin B12 is the only vitamin that contains the element cobalt and its other name is cobalamin. It is produced only by microorganisms and is only found in animal foods.
Since it is not found in plant foods, deficiency can be seen in individuals who have followed a strict vegetarian diet for a long time.
Cobalamin is water-soluble. Its richest food sources include meat, offal, shellfish such as mussels and oysters, and eggs. In animal foods, vitamin B12 is bound to proteins; consuming animal protein therefore also provides vitamin B12.
Functions of vitamin B12 in the body
1. Responsible for the production of blood cells,
2. Participates in the structure of enzymes necessary for tissue growth,
3. Participates in the structure of some enzymes involved in protein, fat and carbohydrate metabolism,
4. Takes part in folic acid metabolism.
Vitamin B12 deficiency
The recommended daily intake of vitamin B12 for a healthy adult is two µg. The need increases with pregnancy, growing age and infectious diseases. Cobalamin deficiency is usually due to absorption problems rather than nutrition.
Deficiency may appear after 1–2 years on a strict vegetarian diet. It can also occur in older adults, people who consume large amounts of alcohol, and those who have undergone sleeve gastrectomy.
Diseases in Vitamin B12 deficiency;
1. Weakness, shortness of breath, palpitations,
2. Anemia,
3. Anorexia, nausea, vomiting, diarrhea,
4. Depression, loss of sensation in the arms and legs and numbness can be seen.
When vitamin B12 is taken too much in the body;
Even when 100 µg of vitamin B12 is taken daily, no toxic or side effects have been detected in the body.
Vitamin B12 is sensitive to light and oxygen but relatively resistant to heat compared with other vitamins. Boiling liver at 100 °C for 5 minutes causes an 8% loss of vitamin B12.
Vitamin H (Biotin)
Biotin is a sulfur-containing vitamin like vitamin B1. It is highly resistant to environmental conditions. It is present in almost all animal and plant foods to a greater or lesser extent. However, vitamin H is also produced by bacteria living in the intestines. Therefore, its deficiency is very rare.
Vitamin H is a water-soluble vitamin and its most important sources are liver, cultivated mushrooms, sourdough bread and eggs. However, consuming raw eggs prevents vitamin H intake.
Vitamin H is bound to a protein called avidin in eggs, which has an antagonistic effect against vitamin H. When eggs are cooked, avidin is denatured and its negative impact on vitamin H disappears.
Functions of vitamin H in the body
1. Acts as a coenzyme in carboxylation and trans-carboxylation reactions,
2. It is a growth factor for almost all living organisms.
Vitamin H deficiency
The recommended daily intake of vitamin H for a healthy adult is approximately 100 µg. Deficiency is very rare because biotin occurs in most foods and is also produced by bacteria in the intestines.
In extreme cases, such as consuming six raw eggs a day for a long time, biotin deficiency can be seen.
Diseases in Vitamin H deficiency;
1. Baldness and skin rash,
2. Depression and hallucination,
3. Muscle pain and dermatitis can be seen.
When vitamin H is taken in excess to the body;
Even when 10 mg of vitamin H is taken daily, no toxic or side effects have been detected in the body.
Folic acid (Folate)
The name folic acid is derived from the Latin word folium, meaning leaf. Although it was first detected in leafy vegetables, it is found in almost all animal and plant foods.
The richest folate sources include liver and other offal, eggs, lettuce, spinach, lentils, sourdough bread and bulgur. About 2–5 mg of folic acid can be stored in the liver. (For more detailed information on folate and other B vitamins in bread, see World Bread Atlas; Varieties, Nutrition and Culture.)
Folic acid is highly sensitive to processing and can suffer losses of 50–95% during food processing and preparation. Eating lettuce without chopping it can therefore help meet folic acid needs.
Functions of folic acid in the body
1. Folate has a significant role in growth and development periods,
2. Necessary for blood cell production and cell proliferation,
3. Vital for the immune system; participates in the formation of antibodies,
4. It is in the structure of enzymes involved in DNA synthesis.
Folic acid deficiency
The recommended daily folic acid intake for a healthy adult is approximately 300 µg. Folic acid deficiency can be seen frequently in pregnant women, premature babies and the elderly. Individuals with gastrointestinal system disorders, malignant tumor patients and alcoholic individuals are in the risk group for folic acid deficiency.
Even if enough folic acid is taken into the diet, insufficient intake of vitamin C and vitamin B12 prevents the use of folic acid taken into the body. Therefore, in folic acid deficiency, adequate amounts of vitamins C and B12 should be taken. Folic acid deficiency shows signs of anemia within 1-2 weeks.
Diseases in Folic acid deficiency;
1. Anemia,
2. Glossitis and diarrhea can be seen.
When folic acid is taken too much in the body;
A high intake of folic acid can cause side effects.
The side effects are;
1. Insomnia and depression,
2. Problems in the gastrointestinal system,
3. Permanent kidney damage.
Note: This article is intended solely for general informational purposes. It does not constitute medical advice or personalized nutritional guidance. Nutritional needs may vary from person to person. Always consult a healthcare professional or a registered dietitian before making any dietary changes.
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Here’s an article that might interest you; All Minerals; Functions, Daily Needs and Rich Foods
Halil İbrahim Akgül
Halil Ibrahim Akgul, Ph.D., is an Assistant Professor of Food Engineering at Bayburt University, where he works in the Division of Food Sciences within the Faculty of Engineering. He received his B.Sc. in Food Engineering from Akdeniz University in 2010, followed by an M.Sc. and a Ph.D. in Food Engineering from Atatürk University in 2015 and 2020, respectively. His formally recognised academic fields are Food Sciences and Engineering, Food Technologies, Dairy and Dairy Products Technology, and Food Microbiology.
Dr. Akgul has more than fifteen years of professional, research, and academic experience in food science. Between 2011 and 2013, he worked as the food engineer responsible for operations at the Pilot Dairy and Bread Factory of Atatürk University’s Directorate of Agricultural Enterprises. This industrial experience, combined with his subsequent academic research, gave him extensive practical and scientific knowledge of milk processing, dairy production, food quality, hygiene, and product development.
His research is primarily focused on milk and dairy products, dairy microbiology, starter cultures, lactic acid bacteria, exopolysaccharides, butter technology, and the physicochemical, microbiological, sensory, and nutritional properties of foods. His studies have examined the quality and fatty-acid composition of traditional butter, aroma formation in butter produced with different starter cultures, raw-milk quality, the characterisation and antioxidant activity of bacterial exopolysaccharides, traditional dairy products such as çökelek and karın kaymağı, colostrum powder, and the use of fruit-derived ingredients in ice cream production.
His academic record includes peer-reviewed research articles published in national and international journals, including Mljekarstvo, Acta Scientiarum Technology, the Journal of Food Safety and Food Quality, the International Journal of Food Engineering, the Atatürk University Journal of Agricultural Faculty, and ATA Food Journal. Four of the research articles currently listed in his university profile were published in SCI-Expanded-indexed journals. He has also contributed to twelve national and international conference papers and presentations covering dairy products, food microbiology, butter quality, fatty-acid composition, starter cultures, exopolysaccharide-producing bacteria, colostrum, traditional foods, and functional ice-cream formulations.
Dr. Akgul has participated as a researcher or adviser in eleven completed scientific and applied research projects. These projects have addressed the modernisation of pilot dairy-processing facilities; the production and quality characteristics of colostrum powder; the physicochemical and microbiological quality of butter and raw milk; the identification of exopolysaccharide-producing lactic acid bacteria; the development and production optimisation of starter cultures for mould-ripened cheese; the standardisation of traditional dairy products; and the use of sloe berry and persimmon fibre in ice-cream production.
His teaching experience spans undergraduate, associate-degree, and graduate education. The courses he has taught include Food Chemistry, Analytical Chemistry, General Chemistry, Organic Chemistry, Fermented Dairy Products Technology, Butter Production and Processing Technology, Healthy Living and Nutrition, Organic Agriculture and Food, Popular Science, Digital Literacy, and Information Technologies. Through these courses, he combines fundamental food chemistry and engineering principles with dairy technology, nutrition, scientific literacy, and the practical communication of scientific knowledge.
He is the founder and Editor-in-Chief of Gıda ve Sağlık, a multilingual digital publication devoted to food, nutrition, health, food chemistry, food microbiology, and culinary science. Through this platform, he draws upon his academic background, teaching experience, research activity, and practical knowledge of food production to present scientifically grounded information in a detailed and accessible form for an international readership.