How your body processes and converts food into nutrition
Annually the U.S Department of Agriculture and the U.S.
Department of Health and Human Services produce Dietary Guidelines for
Americans, which offers advice to promote health and to reduce the risk of chronic
diseases through diet and physical activity. One of the basic messages of the
Dietary Guidelines is that nutrient needs should be met primarily through consuming
foods. In certain cases, fortified foods and dietary supplements may be
necessary to provide one or more nutrients that otherwise might be consumed in
less than recommended amounts. Foods
that provide an array of nutrients and other compounds, within calorie needs,
that have beneficial effects on health. This is of particular importance for
the older adult with set food habits, who with aging, tends to reduce the
amount of calories consumed. Older adults require a high quality diet with
nutrient-dense foods and beverages. This translates into food choices with
sufficient calories and concentrated nutrients. All vegetables, fruits, whole
grains, fat-free or low-fat milk and milk products, seafood, lean meats and
poultry, eggs, beans and peas (legumes), and nuts and seeds that are prepared
without added solid fats, sugars, starches, and sodium are nutrient-dense. We are often feeding smaller appetites
that require additional nutrients due to the physiological changes of aging
that can impair nutrient absorption and utilization.
Important Nutrient Needs for
Older Adults
Protein—Protein
is the foundation upon which every living organism is built. The body does not
store amino acids (the building blocks of proteins), so an adequate daily
intake of protein is needed to supply your body with all the 20 major amino
acids. Adequate intake of dietary
protein is extremely important for tissue repair and healing, especially in the
older adult. Illness, surgery, and
inadequate food intake can result in protein energy malnutrition that can
impair immune function, increase susceptibility to infections, slow wound
healing and increase skin breakdown.
New evidence indicates that eating peanuts and certain tree
nuts (i.e., walnuts, almonds, and pistachios), which are high in protein,
reduces risk factors for cardiovascular disease when consumed as part of a diet
that is nutritionally adequate and within calorie needs. Because nuts and seeds
are also high in calories, they should be eaten in small portions and used to
replace other protein foods. They are so energy dense and tasty that it
can be easy to eat excessive amounts. Choose unsalted nuts and seeds to
help reduce sodium intake.
In 2003, FDA allowed the first qualified health claim for
nuts, suggesting that scientific evidence supports that eating 1.5 ounces per
day of most nuts as part of a diet low in saturated fats and cholesterol may
reduce the risk for heart disease.
Clinical trials with tree nuts have reported favorable reduction in
cholesterol levels, particularly the bad LDL cholesterol that elevates heart
disease risk. This effect has been demonstrated consistently in different
population groups using different study designs and methods.
Carbohydrates and
Fiber — Sufficient carbohydrates are needed to protect protein from
being used as an energy source, however it is recommended that carbohydrate
intake is limited to whole-grain high fiber unprocessed foods. The refining of whole grains involves a
process that results in the loss of vitamins, minerals, and dietary fiber. There are three types of carbohydrates -
sugar, starch and fiber. Both sugar and starch are turned into sugar and since
the body lacks the enzymes needed to digest fiber, it is the only carbohydrate
that doesn’t convert to sugar.
By limiting your daily intake of low fiber highly refined
carbohydrates, you also limit your sugar intake. About 78 million Americans—35 percent of the
U.S. adult population over age 18 —have pre-diabetes, which means that blood
glucose (sugar) levels are higher than normal, but not high enough to be called
diabetes. Carbohydrates in the form of fiber can be found in a variety of fruits,
vegetables, and whole grain foods. Avoid
highly refined grains, as these also can be high in solid fats and added sugars
(e.g., cookies and cakes).
Calcium —
As people age, a decrease in calcium absorption occurs. When the body does not
get enough calcium per day, it draws calcium from your bones. Bone loss also occurs as part of the normal
aging process, particularly in postmenopausal women due to decreased amounts of
estrogen. The elderly population is
especially susceptible to osteoporosis (bone loss) and bone fractures. One out
of every two women and one in four men over age 50 will have an
osteoporosis-related fracture in their lifetime. Many factors increase the risk of developing osteoporosis, including
being female, thin, inactive, or of advanced age; smoking cigarettes; drinking
excessive amounts of alcohol; and having a family history of osteoporosis. Supplementation
with calcium plus vitamin D has been shown to be effective in reducing
fractures and falls (which can cause fractures) in institutionalized older
adults. Some good sources of calcium include yogurt, milk, cheese, firm tofu, canned
salmon with bones, spinach, and rhubarb.
Vitamin D —
Vitamin D is generally referred to as ‘the sunshine vitamin’ as it is
created by our bodies with sun exposure.
However, recent findings of low Vitamin D levels in many patients lead
some to believe that despite getting at least 20 minutes of sunshine daily and
adequate intake of foods high in Vitamin D, a daily supplementation is
necessary to reach optimum levels.
Additionally, if your body doesn’t have sufficient precursors in your
skin to convert to Vitamin D, no amount of sunshine will help and
supplementation will be required. Recent
research has shown a possible link between Vitamin D supplementation and
lowered risk of dementia, heart failure, diabetic neuropathy, and even
cancer. Adequate vitamin D also can help
reduce the risk of bone fractures, especially when taken with calcium
supplementation. Some sources of Vitamin
D are vitamin D milk, egg yolk, salmon, tuna fish, and sardines. You can ask
for a simple blood test from your healthcare provider to determine your risk
for Vitamin D deficiency.
Water — Aging adults
are more susceptible to dehydration due to inadequate daily intake of fluids.
The ability to sense ‘thirst’ is reduced and can significantly decrease optimum
fluid intake to cause dehydration. By
the time one senses they are thirsty, the body is already dehydrated to a
slight degree so that sensing a feeling of thirstiness is actually a symptom of
dehydration. Because our bodies need
water to function normally, when you’re dehydrated you may feel tired, have
trouble concentrating or wind up eating more than usual since our bodies often
misinterpret thirst as hunger. Beverages
that contain caffeine or alcohol can be dehydrating, so be sure you drink plenty
of water to offset your coffee or alcohol consumption. A minimum of 1500 cc’s / day is recommended
for most adults, but there can be lesser requirements for some patients with
certain medical conditions (like kidney disease). Be sure to consult your
healthcare professional for the amount of fluid you are allowed to consume
daily.