What’s In A Diet?
A Multi-Installment Article By Nurse Mark
For that matter, what is a “diet”?
The word “diet” comes, via the Old French word diete and Latin word diaeta, from the Greek word díaita which translates to ‘mode of life’. So, in it’s most basic terms, your “diet” is just the way you live – including what you eat and how you eat it and what you do between the times that you eat.
Some people just eat – they don’t think about it or worry about it, they just eat when they are hungry and stop eating when they are full (or when the food is gone.) They may be healthy, or not. They may be thin or normal weight or fat. For these people “diet” is not something that they associate with health or even think about – it’s just the way they are.
At the other end of the spectrum are the people who are obsessed with food in one way or another: these are the people who are compulsive overeaters, or are anorexic, or bulimic or have other harmful food-related beliefs or practices. For these folks their way of life – their diet – is harmful to their health.
The rest of us fall somewhere in between those two extremes.
Most of us range anywhere from being vaguely aware that diet and health are connected to being actively involved in modifying and hopefully improving our health with conscious and deliberate efforts to change our food intake patterns.
For most of us though the term “diet” doesn’t really mean “way of life” – it just means “way of eating.”
There are also those for whom “diet” means their choices are influenced by their religious, spiritual or philosophical beliefs. Kosher, Halal, vegan, and others follow diets directed more by belief and philosophy than by science or biochemistry. There are even adherents of a dietary philosophy called Breatharianism who claim to be able to derive all the sustenance they need for life through the air they breathe and from sunlight. Not surprisingly, the followers of this rather extreme diet are prone to either “cheat” by eating solid food or to die of starvation – doing both with some regularity.
Why do people diet?
Let’s be honest – in today’s usage the term “diet” has come to have one common meaning. That is, to somehow reduce food intake to produce a loss of body fat.
Oh sure, there are plenty of folks out there who have other food-related goals – athletes, celiacs, diabetics, people with food-related allergies, and so on. But most of us equate the term “diet” to “deprivation” and instinctively understand that “diet” means “things that you would like to eat but can’t because…(insert reason here: overweight, diabetic, allergic, etc.)”
Plenty of “dieters” follow regimens that restrict or promote certain foods or nutrients in order to achieve specific health goals. Some of these regimens are based on solid science and nutritional biochemistry, while others are based more on legend, rumor, marketing, Hollywood starlet testimonials, and so on.
There are plenty of sound medical reasons for altering one’s food intake patterns. Some examples include (in no particular order):
- Weight loss – the granddaddy of all reasons to alter food intake patterns, most popular weight loss diets involve portion control and / or calorie-counting (i.e. food deprivation,) consumption of “good carbs,” fat restriction, and other questionable dietary practices.
- Control of epilepsy – a strategy dating back to the 19th century that was very successful in controlling epilepsy in children involved a very high fat, low carbohydrate, and lower protein intake – it is now very seldom used and is little-known in conventional medicine except as a curiosity.
- Celiac disease – also known as sprue and gluten intolerance is traditionally treated with a diet that avoids gluten, a common food substance that damages intestinal lining.
- Hyperactivity – is often successfully treated with a diet that avoids sugars, synthetic food additives and colorants, and artificial sweeteners – though conventional medical and dietetic wisdom disputes the effectiveness of such diets.
- Diabetes (type II) – while we find this to be an easily corrected condition, many diabetics prefer to follow the conventional recommendations of the American Diabetes Association which favors high carbohydrate / “low glycemic” foods, medication, and frequent blood sugar monitoring.
- Weight gain / muscle gain – many diets are intended to reverse underweight from illness or to promote muscle mass increase in athletes. Most of these diets involve increasing the intake of simple carbohydrates which will result in an increase in fat mass (and a sparing of further loss of muscle mass) but do little to nourish muscle growth. Body-builders sometimes have some especially counter-productive dietary beliefs based more on locker-room legend than on sound biochemistry.
- Cardiovascular health – conventional medical and dietetic wisdom has presented us with a plethora of “heart-healthy” diets – most of which rely on avoidance of fats, salt, animal protein, and sugar, while promoting the consumption of “healthy” and “low glycemic” carbohydrates, fruits, and vegetables. In our experience these diets are poorly effective and even harmful – but they do ensure the need for continued doctor visits and medication to control cholesterol and blood pressure.
- Pregnancy – we’ve all heard that pregnant women are “eating for two” and while this is sometimes an excuse for overindulgence it really is true that without increased intake of fats, proteins, and essential vitamins and micronutrients, pregnancy can be difficult to achieve and even more difficult to maintain. Poor nutrition during pregnancy can and does produce sickly babies and sickly mothers – if it doesn’t cause miscarriage first.
What is the “best” diet?
That’s easy – the “best” diet is one that provides all the nutrients necessary to maintain or improve health, without providing anything that is not necessary.
OK, maybe that’s not so easy after all.
Let’s look at “nutrients” – what we need, and what we don’t, and how much we need. That might make things a little easier… And let’s try to keep this as simple as possible.
In the most basic form, our dietary intake – what we eat – must provide our bodies with energy. Since we are warm-blooded creatures, that energy makes heat, and that heat is measured in “calories” (OK, some scientific types might measure it as B.T.U. or British Thermal Units – but most of us know calories.)
There are three food groups that provide calories when eaten:
- Essential Amino Acids, or Proteins
- Essential Fatty Acids, or Fats
- Carbohydrates (saccharides), from sugars and starches
Alert readers will have noticed that two of those food groups have the term “essential” while the third does not.
Amino Acids – Essential
We are not able to synthesize (or make) a number of amino acids, and for this reason it is essential for us to obtain these building blocks of proteins from dietary intake.
Most microorganisms and plants can biosynthesize all 20 standard amino acids, while animals (including humans) must obtain some of the amino acids from the diet. The amino acids that an organism cannot synthesize on its own are referred to as essential amino acids.
An essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo by the organism (usually referring to humans), and therefore must be supplied in the diet.
Without these Essential Amino Acid building blocks we cannot create (or maintain) muscle – and lest we forget, the heart is one of our more important muscles.
According to the National Academy of Sciences, the average requirement for protein intake is:
- adult women: 48 grams per day
- adult men: 56 grams per day
Pregnant women, children (up to age 18), endurance athletes and sick people have different (usually higher) requirements.
Fats – Another Essential
Like protein, fatty acids (the fancy biochemical way to just say “fats”) must be taken in through our diet – we must have them and we cannot “make” them.
Again from Wikipedia:
Only two EFAs are known for humans: alpha-linolenic acid (an omega-3 fatty acid) and linoleic acid (an omega-6 fatty acid).
These two fatty acids, essential for our health, are absolutely vital for many of our metabolic processes, for the creation of hormones, for nerve function, and the life and health of cardiac cells. The balance between Omega-3 and Omega-6 fatty acids mediates such things as inflammation, mood, cellular signaling, and even activating or inhibiting transcription factors such as NF-κB in our DNA.
How Much Do We Need?
The National Academy of Science recommends a 4:1 to 10:1 (O-6:O-3) ratio. Population studies of long-lived people suggest that a 1:1 to 4:1 ratio is more in accord with healthful living. The Standard American Diet (SAD), typically contains a ratio of 20:1 or higher. The National Institutes of Health recommends that anywhere from from 1 to 12 or more grams of Omega-3 fatty acids be consumed daily depending on a person’s needs.
Omega-3 Oils are derived primarily from fish oil and flax seeds. These essential fatty acids are anti-inflammatory and have a positive effect on cardiovascular disease, including high cholesterol and high blood pressure, allergic and inflammatory conditions (including psoriasis and eczema), autoimmune diseases, cancer, neurological disease, menopause, general health enhancement. Supplementation with Omega-3 Essential Fatty Acids can help “tip the scales” in favor of anti-inflammation.
Omega-6 Oils are found in evening primrose, black current, borage and a number of vegetable oils. Although supplementation is popular, these oils are essential only in very small amounts. Excess Omega-6 oils increase arachadonic acid levels (an inflammatory substance).
The Non-Essential Fatty Acid…
Omega-9 Oils are found in olive, canola, and seed and nut oils. These oils are neutral, producing neither inflammation nor anti-inflammation. Unlike Omega-3 and Omega-6 fatty acids, Omega−9 fatty acids are not classed as essential fatty acids. This is both because they can be created by our body from unsaturated fat, and are therefore not essential in the diet, and because their lack of an n−6 double bond keeps them from participating in the reactions that form the eicosanoids.
Carbohydrates – Not Essential!
If you never ate another carbohydrate again – not a sugar or a starch, not cake nor cookies, or bread, pasta, potato, rice, or another baby carrot or banana ever, you would do just fine – maybe even better than “just fine”!
According to Wikipedia:
Carbohydrates are a common source of energy in living organisms; however, no carbohydrate is an essential nutrient in humans.
And the National Academy of Sciences:
The lower limit of dietary carbohydrate compatible with life apparently is zero, provided that adequate amounts of protein and fat are consumed.
Our bodies are quite capable of meeting our minimal needs for glucose thanks to our liver and a process called “gluconeogenesis” – where our liver will happily make glucose (a carbohydrate) from fats and proteins.
On the other hand, excessive carbohydrate metabolism causes a range of undesirable effects – from inflammation and generation of free radicals, to advanced glycosylated end products (A.G.E.S.), to hormonal disruptions, and more.
So, in summary…
- Everyone is on a “diet” of some sort
- Some “diets” are followed for moral reasons, others for medical reasons.
- The food intake of our “diet” provides us with energy – measured as “calories”
- Of the three food types that we consume for energy, only two are “essential” to life
In future articles we’ll look at some common physical conditions and how those conditions affect our dietary needs, and at some of the more trendy or popular diets with some thoughts on their strengths, weaknesses, and even dangers. We’ll also look at vitamins, minerals, and micronutrients to see how and where they fit into the dietary picture. Finally, we’ll look at how to put all this knowledge together and look at Nutrition Facts Boxes on foods so that we can make better dietary decisions.
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