Nut nutrition, seeds that satisfy

this one is still really hungry
photo: The AquaponicSource

Picture life as a plant. A brand new plant who's hungry and can't just go to the store for a snack.

How do you start growing with no one to feed you?

Happily, your loving mom endowed you with a nutritious snack when you said farewell and blew off or got carried away by some hungry animal.

That snack is made up of actual tissue from your mom, surrounding and even protecting you until you develop your own leaves and roots and start finding your own darned food through them. Thanks, Mom!

Once fertilized, the new plant embryo grows within a seed. Plants need food just as we do, and a seed provides the nutrients and energy used by a growing plant.

A seed, therefore, packs a lot of nutrition, particularly fats, proteins, and other plant nutrients, into a tiny compact package, that can also benefit a person or animal that eats it.

really basic seed structure:
the embryo is the young plant, which will consume
the starchy tissue stored as food, all the while protected
by the tougher outer covering called the seed coat
image: BBC Bitesize

As you might imagine, plants want their seeds to grow up, not get eaten, so seeds often have a hard outer shell or noxious chemical protecting them from predators. Like us, animals that eat nuts and seeds need a tool to break into them or a strong stomach that can tolerate a chemical protection. More on this in a follow-up post.

Full of fat and fiber

Yes, seeds and nuts are high in fats (we could call them lipids, if that sounds better), but that's now Officially OK. The fats in seeds and nuts are mostly unsaturated "healthy" fats, which differ from saturated fats found in red meats and whole dairy products (cheese! ice cream!), and the cholesterol is the "good" high-density lipid (HDL) kind of cholesterol. Fat holds more calories per gram than protein or carbohydrates, meaning nuts provide a lot of energy per mouthful.

They also provide us with antioxidants, fiber, which makes you feel full sooner, and omega-3 fatty acids, which help regulate the rhythm of the heart, which, in turn, prevents dangerous heart rhythms that can lead to heart attacks. Certain kinds of fish (salmon comes to mind) are rich in omega-3 fatty acids, and nuts are one of the best plant-based sources of omega-3's.

Among the many positive components in nuts are Vitamin E and L-arginine, which help our circulation by keeping our arteries clean and flexible. So they can do yoga safely.

Despite the high fat content found in most nuts, people that eat them are not heavier than those that don't. Nuts are filling, so a small amount that can tide us over between meals or make a meal more satisfying may keep us from snacking on even worse temptations. May being the operative word there - I've read that claim endlessly, but sometimes I still want chocolate!

Contains neither grapes nor nuts
image: Wikipedia

Eating nuts makes us less likely to die of cancer, heart disease, and respiratory disease, though medical researchers noting this result in long-term medical studies don't know exactly why. The link between eating more nuts and having a lower risk of these problems holds among different races and nations.

Nuts and seeds contain protein as well, but lack certain amino acids, so vegetarians need to complement nuts with other foods (e.g. legumes) to get the full benefit.

With all the benefits we gain from making nuts a consistent part of our diets, scientists are experimenting with techniques to lessen the severe allergic reactions some people experience from eating nuts. The techniques include women eating nuts while pregnant and feeding small amounts to infants to build up their tolerance.

What we call nuts actually include both dried seeds and dried fruits. Technically, nuts are dried hard-shelled fruits with a tough "pulp" and a single seed that does not open on its own, like an acorn or hazelnut, but commonly, we also include peanuts (which are beans) and a number of seeds (e.g. walnuts and almonds) when we talk about eating nuts.

Humans, of course, are just one of many animals that eat nuts and seeds, so stay tuned for a follow-up post on seed predators from around the animal kingdom. By eating seeds, these animals get good bang for their foraging buck, and their eating patterns affect where and when plants grow. Important stuff.

Read more on nut nutrition

New York Times article on nuts as a "nutritional powerhouse"

Wikipedia post on nutrient content of nuts

Mayo Clinic post on nuts for better heart health (who knew?)

British Journal of Nutrition scientific analysis of energy and macronutrients found in nuts

Full citation:  Brufau G, Boatella J, and Rafecas M. 2006. Nuts: source of energy and macronutrients. British Journal of Nutrition, 96, Suppl. 2, S24–S28. DOI: 10.1017/BJN20061860