Breast milk from women in regions where the first humans likely emerged suggests that Western diets — with their high amounts of carbs, sugars, salts and oils — go against the optimal human diet.
That conclusion comes from a new study that also suggests infant formula guidelines, which are based on Western dietary recommendations, need reassessment.
"It is somewhat strange to first drastically deviate from what we as Homo sapiens derive from in an evolutionary sense, then, because of this deviation, we get all kinds of new diseases that many blame on environment, notably diet, and then we set recommendations on the basis of this abnormal diet!" author Frits Muskiet told Discovery News.
Muskiet is a scientist in the department of Pathology and Laboratory Medicine at the Netherlands' University Medical Center Groningen. He and his colleagues conducted chemical analysis of milk obtained from 20 mothers living on the island of Chole, Tanzania. Some of the oldest human remains have been found in this region.
For comparison, the researchers then studied milk from women living in four different tribes in the Tanzanian inland.
Their findings have been accepted for publication in the journal Prostaglandins, Leukotrines and Essential Fatty Acids.
Chole's inhabitants eat large amounts of coconut, fish, vegetables, fruits and occasional flying fox meat. The other tribes studied eat foods often associated with Western diets, such as processed carbohydrates, red meat and corn oil.
The chemical analysis found mothers' milk from Chole contained high amounts of lauric acid, an unsaturated fatty acid often derived from coconuts. The tribes with more Western diets showed fewer fish oil fatty acids and high concentrations of linoleic acid, a polyunsaturated fatty acid that is a component of many vegetable oils.
Infant formula guidelines in most countries more closely match the inland milk, but Muskiet and his team believe the Chole milk and diet are likely more ideal.
So is the Chole level of activity.
"They are very fit," he said.
Muskiet explained that the human genome changes, or adjusts, to its environment with a rate of about ".5 percent per million years," so although many human lifestyles have dramatically changed from those in Paleolithic times, the human genome is still adapted to the conditions then.
Loren Cordain, professor in the Department of Health and Exercise Science at Colorado State University, said he agrees there is an "evolutionary basis for optimal diet and hence the range of values for fatty acids, which would have been found in the milk of our pre-agricultural ancestors."
But he thinks the jury is still out on whether the earliest coastal humans regularly ate seafood, "as the technology to efficiently capture fish (hooks, weirs, seins, nets, barbed spears, etc.) only came into being in the past 40,000 to 70,000 years."
Muskiet said people today don't have to live like cavemen to reap the benefits of the past.
"The point is that we may enjoy more years in health if we adapt our lifestyle to that of our ancient fathers and mothers according to modern Western habits," he said.
"You don't have to dig tubers and run after antelopes, but you can make healthy food choices in a modern supermarket...and you can visit the gym or take a daily walk or do some biking," he added.
Special Thanks to Discovery Channel