Trial by food, not by supplement

Rizzolo’s trial of 143 participants, all of whom were over the age of 65 and diagnosed as prediabetic, were put on a nutrition plan to reduce their risk of developing type-2 diabetes, a disease that afflicts 14% of the Spanish adult population.

However only one of the two groups added 200 grams (approximately two cans) of sardines with bones, in olive oil per week. That group had 37% of participants at a high risk of developing diabetes at the start of the trial, and only 8% remained at high risk by trial’s end, compared to a reduction to 22% from 27% in the group that didn’t consume sardines.

Improvements were also seen in other important biochemical parameters, such as a reduced insulin resistance index, increased HDL cholesterol, increased hormones that accelerate the breakdown of glucose (adiponectin) and decreased triglycerides and blood pressure, amongst others.

Sardines are rich in omega 3, vitamin D, and calcium. They’re also rich in taurine, a semi-essential amino acid that has been shown in some studies to have interesting hypoglycemic effects, as well as being notably deficient in new type-2 diabetic patients, suggesting a possible link between the two.

The only other oily fish likewise rich in taurine, in case sardines aren’t for you, are anchovies, though the topic hasn’t been researched thoroughly.

However Rizzolo warns the reading public, understanding how many people take fish oil supplements, that the effect conferred by a food or a given nutrient is by no means equaled to a supplemented nutrient of the same kind.

“When a food produces a beneficial effect we want to know who is responsible and, as consumers, we usually want to identify a nutrient,” explains Rizzolo. “A food is something much more complex as well as what its consumption produces in our body. When we eat quinoa, we are not eating carbohydrates, we are eating a set of more than 50 macro and micronutrients in specific proportions that, when consumed in the food matrix itself, will generate a different effect”.

This food matrix effect is partly why it is difficult to pin negative health outcomes on dairy products — because different dairy products, while containing similar nutrients, often in similar amounts, have different food matrices.

“The combination of nutrients not only adds their actions but also creates synergistic actions that modify their performance. If we add to this the structure in which they go, there is also a differentiation with respect to what we can find taking supplements,” says Rizzolo.

Even though they have been shown as a possible link to increased heavy metal toxicity in the blood, Rizzolo adds that even four cans of sardines a week is probably okay, though she suggests varying seafood intake throughout the week so as to maximize the greatest number of positive nutrients.

Her work with the small fry will continue as she hopes to uncover the compliment of effects sardines have on the gut microbiota. Her first research, a total census of bacterial species, is near to being completed. WaL