Personalized platform potential: Genetic differences may impact how people digest starch

06 May 2019 --- A new Cornell University study has found that a person’s genetic makeup could alter their gut bacteria, which in turn impacts how they digest food – in the case of this study, starch. People with a high number of copies of a gene called AMY1, which expresses a salivary enzyme for breaking down starch, correlated strongly with a certain profile of gut and mouth bacteria. The gene could have given certain groups nutritional benefits in times where calories were scarce, such as during cold seasons and famines, the researchers note. Now, medical professionals could take a patient’s AMY1 gene copy number into account when giving personalized dietary advice.

The results of the study, published in Cell Host & Microbe, highlight the need for personalized nutrition, says Angela Poole, Assistant Professor in the Division of Nutritional Sciences. Other researchers have also associated the gene with glucose response to meals, insulin resistance and body mass index.

Diet is arguably one of the most important determinants of health, but there remains confusion over what to eat to optimize health and performance. Current dietary recommendations are based on a limited “one-size-fits-all” health model. Yet, the case for personalized nutrition approaches is growing as novel research continues to identify how an individual’s genetic makeup, for example, can alter their nutritional profile and subsequent dietary needs. Personalized approaches – or nutrigenomics – have also swiftly caught the attention of the industry and consumers alike, with Innova Market Insights pegging “Eating for Me” as one of its top trends for 2019.

According to the Cornell study, a family of bacteria called Ruminococcaceae proliferates in the intestines when more of this salivary enzyme – called amylase – is available. The bacteria are known to break down resistant starch to render it digestible, something human amylases cannot do. Importantly, degrading these hard to digest starches can provide additional nutritional benefits.

In prehistoric times and thereafter, people with more copies of this gene may have benefited when food sources were limited, as it likely provided additional nutrition from starch foods, the researchers explain.

The results of the study highlight the need for personalized nutrition, say the researchers.In the study, Poole and colleagues examined existing genetic and stool sample data from approximately 1,000 British participants. Looking for evidence of whether AMY1 gene copy numbers influence the microbiome, the researchers examined the results from a subset of 100 people from the group: 50 with a predicted high copy number (top 5 percent) and 50 with a low copy number (bottom 5 percent).

They found that high AMY1 gene copy numbers correlated with a certain profile of gut bacteria.

A collection of 100 US participant were then studied. Within this group, there was a distribution of AMY1 levels between two and 30 copies. The team also collected stool data and identified bacteria associated with high and low AMY1 gene copy numbers.

One-quarter of these study participants were then placed on a standardized diet for two weeks. “I wanted to make sure they were eating the same thing, and that they were eating starch,” Poole says. Afterward, the team collected saliva and stool samples and found that, in the gut, the results matched those from the British study.

Personalization: The future of nutrition?
Personalization in the nutrition space is gaining traction. Wearable technology means that we know more and have more personal health Key Performance Indicators (KPI’s) on hand than ever before. At the same time, the growing role for nutrigenomics as a science means that ever smaller demographic groups are being targeted, while technologies that include artificial intelligence (AI) and 3D printing make customization ever more prevalent. 

A Vitafoods Europe survey found last year that industry interest in personalized genetic testing and nutrigenomics is growing, with 14 percent of respondents saying nutrigenomics would be a key trend over the coming year – up from 8 percent the previous year.

There has been a spike in technology that taps into the personalized space, such as DSM and digital health company Mixfit’s foray into the arena. Dr. Lisa Ryan, an Irish researcher from the Department of Natural Sciences at Galway-Mayo (GMIT) in Ireland, has also highlighted the potential that technological advances, such as wearable nutrition and microbiota mapping tools, hold for the nutrition industry. 

However, Nard Clabbers, Senior Business Developer Personalized Nutrition at TNO, tells NutritionInsight that the industry must not wholly focus on technology, as the psychological and social aspects of behavioral change are at least equally, if not more important, to personalized nutrition. He also highlights the need for robust science to back up such approaches, especially when it comes to the microbiome. 

“I have often said that one of the threats of personalized nutrition is overpromising because that can lead to unsatisfied consumers that feel cheated. I think that risk is very true in the microbiome world,” he explains.

The potential of the microbiome in personalized nutrition platforms has attracted notable investment. Bio-Me, a start-up specializing in rapid gut microbiome analysis, has entered into an agreement with an unnamed “top” consumer healthcare company associated with the large-scale Nord-Trøndelag Health Study (HUNT). Also, Carbiotix, a therapeutics company leveraging low-cost gut health testing and microbiome modulators to unlock the health-boosting potential of the gut microbiome, closed its latest funding round in April, bringing the total funds raised to €1 million (US$1.2 million) over four years. In partnership news, DSM has joined with digital health provider Panaceutics to bring to the market “affordable” personalized products explicitly geared towards health and wellness.

The space for personalization in nutrition is being embraced by industry and consumers. The sound scientific backing needed to ensure that consumers do not feel “cheated” can come from studies such as Cornell University’s and the investments coming into the area can also aid such findings.

By Laxmi Haigh