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What are the side effects of vitamin B?

vitamin b

Vitamin B comprises 8 types of vitamin: B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B8 (biotin), B9 (folic acid) and B12 (cobalamin). They’re assimilated through food and the digestive wall. They’re found in food such as seeds, nuts, cereals, legumes, pulses, products of animal origin (meat, fish, shellfish, dairy products, eggs). Needs vary from one person to another yet, for information purposes, here is the recommended daily vitamin B intake for women and men:

Type of vitamin B For women For men
B1 1,1 mg 1,2 mg
B2 1,1 mg 1,3 mg
B3 14 mg 16 mg
B5 5 mg
B6 1,3 mg
B8 30 mcg
B9 400 mcg
B12 2,4 mcg

Vitamin B deficiency can cause many different symptoms: digestive disorders, skin issues, anaemia, fatigue, as well as neuropsychiatric disorders. So, it should be taken seriously. You can think about taking a vitamin B supplement: intravenous injections are perfect to relieve symptoms effectively. These injections, administered directly into the bloodstream, provide the body with the vitamins it needs rapidly. Here, at YuBoost, we propose several types of IV therapy that combine vitamins, minerals and antioxidants. As various side effects may occur in the event of a vitamin B overdose, you should ensure you get a reasonable daily intake and only opt for supplements when necessary.

Gastrointestinal disorders

Gastrointestinal disorders are common in the event of a vitamin B overdose, in particular in seniors. They may occur in the form of stomach ache, nausea or diarrhoea. Some patients also lose their appetite. Excess intake of vitamin B3 is generally the cause of these digestive disorders.

Skin reactions and allergies

Skin reactions may occur when there’s an excessive intake of vitamin B3. This vitamin has an upper intake level (maximum daily dose) that must be complied with scrupulously. These transient rashes most often result in inflammation of the skin, redness, itching, sensitivity to light and sometimes urticaria.

Aside from overdosing, allergic reactions may appear, irrespective of the type of group B vitamin ingested. They can be similar to the skin rashes mentioned above, but can also result in Quincke’s oedema (angioedema). This involves sudden swelling of the mucous membranes and skin around the neck and face, and can lead to a medical emergency if the airways are affected. This is why we recommend you always seek advice from specialists like the YuBoost team.

Neurological and psychological disorders

Excessive vitamin B intake can have a negative impact on mental health and cause mood swings, restlessness, panic attacks and depression. Neurological effects are also likely to occur, in particular in the event of vitamin B6 overdosing. These appear in the form of feelings of numbness or tingling in the arms or legs. Here, at YuBoost, our specialized nurses hold an interview beforehand with each patient to talk about these different risks.

Impacts on sleep and blood pressure 

Other side effects that may be felt in the event of overdosing include impaired sleep, in particular in the case of excess vitamin B12, which tends to increase energy levels. Moreover, variations in blood pressure may be noticed: it may be particularly high (hypertension) or low (hypotension), depending on whether it’s an overdose of vitamin B1 or B2, and may cause long-term damage to the cardiovascular system.

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