Biotin, or vitamin B7, is an important water-soluble vitamin for a number of different physiological reactions in our body. It is something we can not produce for ourselves so we need to make sure we eat foods rich in biotin to make sure we meet our daily quotas . In the event you do not meet your daily target, you may start to notice wholesale changes throughout your body. Some of the more obvious signs that you are suffering from a biotin deficiency would be hair loss, dermal changes, brittle nails and sugar intolerance . It is a big reason why there has been a biotin craze in the supplement industry where customers are encouraged to buy biotin for hair growth when needing a hair loss treatment, how biotin can strengthen your brittle nails and even some of the biotin benefits for your skin . We have found in previous investigations that biotin supplementation for this category is only effective if you are suffering from an overt biotin deficiency. Here, we will tackle what are the causes of biotin deficiency in the first place.
When it comes to biotin deficiencies, thankfully, the majority of the population will be able to consume enough food in the foods they normally eat to achieve what they need. When you look at expecting mothers, however, this is where biotin deficiencies are more common and much more significant. It is believed that approximately 50 percent of expecting mothers have increased levels of 3-hydroxyisovaleric acid (3-HIA). This is a metabolite of a reaction that biotin is required to start and as a result, it is suspected that women in this category could be suffering from marginally low levels of biotin.
Marginally low levels of biotin are not something to dismiss too easily because of how important sufficient levels of biotin is to fetal growth and development. When biotin levels are too low, several studies depict situations where fetal demise occurs during the pregnancy. This is due to the fact that insufficient biotin is teratogenic so mothers need to make sure they are eating enough to meet their dietary needs. 
Most of the biotin we consume is absorbed along our intestinal tract while excess biotin is excreted in urine. Due to a large amount of biotin that is processed in the mother's intestinal tract, her baby is at risk of not receiving enough biotin.  Biotin deficiencies have been linked to spontaneous abortions, growth retardation, mental disabilities and nerve problems so it is imperative that mothers make sure they are eating enough biotin. 
Poor Dietary Intake
Another potential cause of biotin deficiency stems from the food choices we make in our everyday lives. A lot of foods available at the grocery store have moderate levels of biotin in them so routine balanced meals will be able to meet your daily recommendations without much of an issue. Patients that fail to meet these quotas usually have some underlying deficiency because of conscious decisions they are making in the foods they eat.
One group that I am referring to would be bodybuilders or those looking to increase their protein intake. Common techniques that people in this category will use would be to ingest raw eggs in order to boost their morning protein intake, but enzymes in raw eggs called Avidin are biotin's worst nightmare. This protein binds to biotin and prevents it from being absorbed in our intestinal tract so if you routinely eat raw eggs in your diet; you are preventing your body from taking in an essential factor. 
Chronic alcoholics also are people who are at risk for biotin deficiencies for similar reasons. Alcohol does not contain any Avidin but when you constantly consume alcohol, you are greatly interfering with the ability of your intestinal tract to absorb biotin. Their diets are typically poor as well so you will need to make the problem worse from two different perspectives. 
Gastritis or Recent Surgery
The last substantial cause of biotin deficiency that is relatively common in the population would be missing biotin intake after some type of intestinal or gastric operation. Any type of surgery or disorder that can produce a problem with absorption is likely to predispose patients to miss a number of vitamins and minerals, including biotin. Bariatric surgery is one of the leading causes of current increases in the number of patients suffering from biotin deficiencies as patients try to combat morbid obesity so be aware of potential risks that you could experience. 
Another of the causes of biotin deficiency could be inflammatory bowel diseases like Ulcerative Colitis or Crohn's Disease. Even if their pathologies are different, both lead to persistent diarrhea and patients will often suffer from deficient levels of biotin as a result.  Any type of disorder associated with chronic diarrhea, like Celiac Disease, Irritable Bowel Syndrome or chronic diarrhea itself all can produce these same effects.
All in all, biotin deficiency is something that is quite possible in a number of patients. Even if supplementation, like biotin for hair growth as a hair loss treatment is possible, some of these more chronic conditions need to be addressed first before patients start to have higher levels of biotin.