Bees have known it all along: simply by feeding a particular larva royal jelly, they can change its destiny from worker to queen. Beyond insects, scientists are today revealing the mechanisms behind the power of food in shaping human life.
“Nutrition can determine who you are,” said Navin Sharma, Programme Director (Biofuels) at the World Agroforestry Centre (ICRAF), at a recent seminar.
“Diet influences cell division, and dramatically affects health, appearance and longevity. Certain diseases and medical conditions and ailments can be held at bay, or accelerated, depending on a person’s diet,” he said.
“The exciting thing now is that biological scientists are finding out the specific ways molecules found in the food we eat interact with our bodies at the cellular and genetic levels.
“And epigenetics—the study of heritable changes in gene activity that are not caused by changes in the DNA sequence— is saying that nothing is more powerful than diet to life outcomes,” he continued.
For instance, it was shown in the mid-nineties that a pregnant woman’s diet effectively ‘blueprints’ their child’s health, influencing the medical conditions the child is likely or unlikely to experience in adulthood. And in more recent experiments with mice, researchers at the University of Utah were able to produce offspring that was leaner and healthier from a mother genetically predisposed to obesity, cancer, diabetes and a short lifespan. They achieved this by supplementing the pregnant mouse’s diet with zinc, methionine, choline, folate and vitamin B12. Diet, evidently, overcame the mice’s genetic predisposition.
According to Sharma, therefore, “nutrition appears to play an even bigger role than your DNA.”
Advances in epigenetics and mimetics
Thanks to technological innovations, the exact pathways particular bioactive food components interact at the cellular and DNA level can for the first time be unveiled.
In the case of bees, scientists have established that a diet of royal jelly ‘silences’ (prevents the expression of) a particular bee gene called DNMT3, which would cause the larva to emerge as a worker bee; a larva with this gene silenced emerges as an adult queen with ovaries and a larger abdomen for egg laying (worker bees are sterile). Queen bees also lives 40 times longer (2-3 years) than genetically identical worker bees on an ordinary diet.
The metabolic pathway of the world’s favourite beverage has also been worked out, showing how theanine, an active molecule in tea, reacts with human brain receptors to activate alpha waves. This type of wave is associated with an “awake but relaxed” state. (Caffeine in coffee, on the other hand, excites beta waves which correspond to a “wakeful, excited” state).
Another rapidly emerging field is mimetics, which looks at how certain foods mimic unrelated experiences or functions. The compound resveratrol found in red wine, for instance, has been shown to mimic the effect of dietary restriction; this explains the action of red wine in regulating certain cardiovascular ailments.
Not surprisingly, researchers in this field are now looking into products that you could eat to mimic the effect of exercise—the plan is to develop an “exercise pill” that people can take in place of a good workout!
Natural products that alter the taste of food are being also studied. One “miracle fruit” is Synsepalum dulcificum, a West African berry that has a molecule, miraculin, that binds to the tongue's taste buds and causes sour foods to taste sweet. A plain meal served along with a glass of the berry's juice turns—as if by magic—tasty.
Potential of tree products
“Trees have always been a source of wonder molecules. Aspirin and quinine are some game-changing examples,” said Sharma.
And in the new world of advances in nutrition, trees are coming into their own.
“New tree products will help us ‘de-junk the junk’,” he stated.
Amla, or Indian gooseberry (Emblica officinalis), has long been used in Ayurveda. The fruit contains between 700 and 1,000 mg of vitamin C per 100 grams, 13 times more than oranges. It is a powerful immune booster with anti-aging properties, related to its exceptionally high Vitamin C content.
Coconut and maple tree sap are being used to produce sugars with low glycemic index (GI) rating, far healthier than regular white sugar. Allanblackia kernel oil has high levels the heart-healthy stearic and oleic acids; this African forest species is being domesticated by ICRAF and partners under the Novella partnership of Unilever and public- and private-sector actors.
“Agroforestry has the complete nutrition pyramid,” said Sharma. “It combines crops, trees vegetables and livestock, and has great promise to meet the global aspiration of sustainable agriculture, food security and nutrition.”
“Trees provide an array of fruits, vegetables, nuts, and other products high in vitamins, minerals and bioactive compounds.”
Examples are peach, jackfruit, tamarind and dates, all high in methionine and niacin (Vitamin B3). Baobab is increasingly being called a ‘superfood’, for the nutritional punch it packs. And a recent article called jackfruit a ‘miracle fruit,’ on account of its dense nutrition and versatility.
Highly bioactive components from trees are the basis of most modern and traditional medicine; a good example is Moringa olifera, which has been widely researched for its myriad nutritional, health and medical benefits, such as boosting the immune system, fighting cancer, and combating bacterial infection and inflammatory conditions.
According to Sharma, nutrition is evolving from a ‘basic nutrition’ perspective concerned with maintaining normal human functions, to a ‘prescriptive’ model which involves modifying the diet to achieve specific health, vitality and longevity outcomes.
And trees, in forests and widely grown on farms, will play an increasingly important role in resolving the ‘Nutritional Double Burden,’ — the dual global challenge of malnutrition and hunger in the global South, and obesity, nutritional deficiencies and chronic diseases in the global North, said Sharma.
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Download Dr. Navin Sharma’s presentation: Nutrition Beyond Calories and the Role Trees can play
Related stories:
The little-understood indigenous African fruit trees
Trees and food security in Africa; what’s the link?
Include indigenous fruit and vegetables in school feeding programmes nationally
On the forest’s margins: bringing the benefits of trees from the wild into the farm
A bit of baobab a day keeps the doctor away: wild fruits help solve Africa’s malnutrition crisis
