Age and weight you have mentioned is that of an child.
In an adult ,low
vitamin B12 defeciency of 90 mcg. Should be treated with injection cyanocobalamin 1000mcg once every week for 4 weeks,There after either you can take injection cyanocobalamin 1000 mcg once a month or daily oral cyanocobalamin at doses of 1,000 μg are as effective as monthly intramuscular injection .
Next Steps
since you have not mentioned the value of lipids profile ,it's not appropriate to give opinion
Health Tips
B12is mainly present in animal-source foods (meat, fish, eggs, milk) and foods fortified with
B12,
modification lifestyle and food habits daily exercise will help you to control cholesterol and
triglycerides if moderately raised