• Your Genetic Inheritance

You may be genetically predisposed to being a poor methylator. Many genes are involved in controlling the methylation cycle, and differences in these genes have been discovered in people with autism.

Genes direct enzymes, enabling chemical reactions to occur. The process of methylation depends on several enzymes as well as specific nutrients.

One of the most important nutrients needed for methylation to occur is vitamin B9, otherwise known as folate. Many different types of folate exist in nature, but your body needs the folate to be in a form it can easily use for efficient methylation to occur.

Variants in a gene known as MTHFR, thought to affect up to a quarter of the population, can affect the production of an enzyme needed to produce the active form of folate. Research has found this genetic variant is higher in children with autism.

It’s worth remembering folic acid is not the same as folate, although the terms are often used interchangeably. Folic acid is a synthetic form of vitamin B9 added to food and used in some supplements, and it first needs to be converted to an active form before it can be used.

Although a genetic variant can make you more likely to have issues with methylation, whether or not this genetic tendency is expressed depends on environmental factors such as nutritional deficiencies, stress, environmental toxins and the condition of your microbiome, the population of bacteria resident in your gut and elsewhere in your body.

• Your Immune System

Scientists believe the immune system sometimes produces antibodies binding to the receptors responsible for transporting folate into the brain. This means these receptors can no longer respond to folate, even when it’s been converted to its active form, so it can’t access the brain to help with methylation there.

Children with ASD have been found to have more of these antibodies compared to children without autis

• Your Toxic Load

Toxic metals such as mercury and lead can block the methylation cycle, while problems with methylation can mean your body struggles to detoxify heavy metals and other toxins effectively.

On the other hand, genetic mutations can mean some people are better at detoxifying unwanted substances than others.

Scientists estimate there are over one thousand different species of bacteria, fungi and viruses living in your gut, all coexisting harmoniously. One of the fascinating things about your microbiome is it’s completely personal to you. Although certain species of bacteria tend to be present in everyone, the dominant species in your microbiome, the number of different types of bacteria and their various quantities are all influenced by your diet, lifestyle and health history.

Your personal bacterial population all emit different chemical messengers, because certain species are better at producing some chemicals than others. Friendly bacteria produce anti-inflammatory chemicals. Other bacteria are not so beneficial, releasing chemicals encouraging inflammation, and ideally these are kept in check by your friendly bacteria. Think of a garden where plant-eating pests are naturally kept in check by other insects such as ladybirds. When this balance becomes upset in the natural world, plants are damaged by aphids, while imbalances in your microbiome mean unfriendly bacteria increase inflammation in your body, disrupt digestion and upset your immune system. Dysbiosis of your microbiome can also lead to oxidative stress, resulting in DNA damage and ageing, and is generally considered to cause an increased risk of disease.

In your microbiome ecosystem, diversity definitely matters, with people having a wide variety of bacterial species more likely to enjoy good health. In studies, researchers found people suffering from chronic, non-infectious diseases tended to have a less diverse microbiome. As in a natural ecosystem, diversity equals resilience – if one species dies out, it’s less likely to have an impact than if there are only a few species in a particular community.