Multiple factors, both dietary and non-dietary impact one's risk of bone fractures. When it comes to vegans, I believe that the biggest dietary factor is poor status of vitamin B12. Almost without exceptions, studies have shown that vegans have the lowest serum/plasma vitamin B12 and the poorest status of other markers of this vitamin, such as homocysteine. Vitamin B12 impacts the risk of bone fractures directly and indirectly through homocysteine in a number of ways. I believe that if vegans improve their vitamin B12 status they will greatly reduce their risk of bone fractures. The easiest and most reliable ways to do it is be regularly using vitamin B12 supplements.

Homocysteine is a compound the body makes, which is essential for various functions. However, as is the case with cholesterol, which the body also makes and which is also essential for our health, elevated homocysteine concentrations have been associated with a variety of adverse health conditions, such as cardiovascular disease, diabetic complications, including retinopathy and neuropathy, bone fractures, neural tube defects, and many others. Homocysteine concentration is impacted by intake and status of several nutrients, including an amino acid methionine, vitamins folic acid, B12, and B6. Homocysteine may be elevated in the presence of some health conditions, such as renal insufficiency. The best way to keep homocysteine in check (below 10 mcgmol/L) is to ensure adequate intake of the above-mentioned vitamins.

Symptoms of vitamin B12 deficiency in infants and children are many. Some of the most common pediatric symptoms are listed in the table below.

As shown below on the graphs, inadequate intake and excretion of iodine among vegans is quite common. To ensure adequate intake, vegans can do several things. 1. They should make sure they ingest iodized salt. This in itself may or may not be enough. 2. They can ingest seaweeds. However, the content of iodine in seaweeds varies considerable with some seaweeds containing mega doses of iodine, which may result in iodine toxicity. Thus, intake of seaweeds should be limited. 3. They can use iodine supplements, in the dose of 150 mcg/day.

As you can see on the graph below, a specific type of iron supplement, called iron bisglycinade is as effective as the most widely used type of iron supplement even when only half of the dose of iron are taken. In addition, this type of iron supplement is associated with fewer and less severe adverse gastrointestinal symptoms.

Soy-based meat substitutes may be acceptable to use sparingly especially as people transition from a meat-based diet to a vegetarian one. These products generally speaking contain lower amount of fat and they do not contain at all or contain only small amounts of cholesterol and animal protein. However, these products are highly processed and they generally contain high amounts of sodium. In addition, as shown below, a study found high prevalence of bacterial contamination of some of these products. Thus, consumers should ensure they are well-cooked before using.

Although there are those who claim that we should always use methylcobalamin and that we should never use cyanocobalamin, I am convinced that using the right dose is more important than whatever type we choose. Each type, whether methylcobamain, cyanocobalamin, or any other type, has advantages and disadvantages. There is also some evidence that cyanocobalamin might be better than other types as it is the most stable and has a good absorption rate. In addition, cyanocobalamin is the most widely available and it is the cheapest. However, any one type can be used.

This question is not easy to answer. However, a few things should be kept in mind when ordering a good dose. First, only small percentage of the dose is actually absorbed. Thus, the dose should be higher, for some individuals, considerably higher, than the daily recommendation. Second, when deciding on a dose consider how old you are and whether or not you have any health condition or do you take any medication that may interfere with vitamin B12 absorption. For example, a drug metformin, prescribed to patients with diabetes and prediabetes interferes with absorption of this vitamin. Also, individuals with gastrointestinal health conditions , such as Celiac disease, or irritable bowel disease, may not be able to absorb as much of the vitamin as healthy individuals. Children should be ingesting lower doses than adults. It would be prudent to verify serum concentration of vitamin B12 and homocysteine after several months of taking a supplement and adjust the dose if needed.