by ADMIN on OCTOBER 15, 2012
(Source: Mirriam Webster)
When people think of bone strength, vitamin D and Calcium normally come to mind. While these are an important part of keeping your bones healthy and strong – there’s new research showing that you might be weakening your bones by eating too may grains and animal proteins.
There is a line of research going on right now looking at whether or not a highly acidic diet causes poor health and disease. What does this mean? When we eat foods, they are broken down into components that may be either more acidic or more alkaline (base). The foods themselves may not be acidic, just the components they’re broken down into.
One area that is getting more attention now is if a more acidic diet is causing our bones to become weaker.
A little Biology:
Acid-Base Balance
Our bodies tightly regulate the acid-base balance in our blood, as well as intra- and extra-cellular fluids, to stay between 7.35 and 7.45. This homeostatic balance is crucial because going above or below this range can be life threatening. The acidity and alkalinity of our blood is affected by several factors including toxins from the environment and disruptions in the mechanisms that regulate the balance.
But one of the biggest acid-producing entities is food; specifically those foods with sulfur-containing amino acids.
{Amino acids are the building blocks of proteins. There are 21.}
Helping to compensate for imbalances in homeostasis are: The lungs, which get rid of acidic CO2 by ‘blowing it off’; and The kidneys, which expel acidic hydrogen ions via urine and reabsorb bicarbonates which are alkaline. There are several other buffering pathways as well.
Calcium Homeostasis
Most calcium in the body is stored in our bones and teeth; however, one percent (1%) of calcium is found is our blood and intra- and extra-cellular fluids. This one percent is indispensable for life. It helps cells send communication signals and transport compounds across cell membranes; helps with hormone function; and is imperative to nerve transmission and regulation of heart muscle function.
Calcium is alkaline (a base), and research is now finding that extra calcium helps with maintaining the acid-base balance in the body. So when the body senses it’s environment is getting too acidic, bones (and muscle!) are broken down to release calcium to help bring the body back into an acid-base balance.
Obviously, the break down of bone and muscle is not ideal for health.
What foods are Acidic?
Although lemons, limes, orange juice, and other citrus fruits are acidic tasting, these are not the foods that cause a change in our acid-base balance. Rather, it’s primarily proteins and grains that are broken down {metabolized} into acidic compounds such as sulfuric acid. Fruits and vegetables are primarily broken down into more alkaline compounds, such as bicaronate, which help to neutralize acid. Some vegetable proteins are slightly acidic, however, they are much less acid-producing than animal proteins.
So the hypothesis is that when we eat too much animal protein and grains (such as bread, cereal, rice, pasta, cookies, doughnuts, tortillas, cupcakes, and similar foods) we are creating a more acidic environment. Because the body cannot risk a big change in pH (levels of acidity), it immediately begins to buffer the acid by adding alkaline compounds – such as calcium from our bones and muscles.
Study: Bess Dawson-Hughes, director of the Bone Metabolism Laboratory at the Jean Mayer Nutrition Research Center on Aging at Tufts, has completed several studies on acid and bone loss. One placed people on an acid-producing diet (a diet high in protein and grains). The researchers then gave an alkali such as potassium bicarbonate. The results showed drops in bone marker turn over (which means that less calcium was being leached from the bone), as well as a drop in nitrogen excretion (which is an indication of muscle wasting, meaning that less muscle was being broken down). The effects occurred immediately.
In a second three-month study, participants on acid-producing diets were given bicarbonate foods (alkaline). This study found that not only was there a reduction in bone turnover, but those who got a higher dose of the bicarbonate foods actually improved their double leg press strength and power. This means the less acidic diet helped to maintain muscle mass.
What does this mean for You?
While there is much more research that needs to be done before strong recommendations are put out, the evidence is growing that we need to change our diets away from the type Western eating pattern, which emphasizes proteins and grains.
Many American’s eat up to 60% more protein than what they need. As a nation, we’re also eating far too many processed grains. Just go to your local Italian restaurant and see how high they pile the pasta – it’s enough for 4-6 meals! Both of these foods have become the centerpieces of our meals, when they should simply be a compliment.
Furthermore, processed grains, such as cookies, crackers, white breads, sugary cereals, muffins, chips, white pasta, pastries, doughnuts, bagels, and candy, are all devoid of nutrients that help keep you healthy. Yet they are packed with nutrients {saturated fats, trans fats, sodium, and sugar} that cause diseases and harmful internal inflammation.
Fruits, vegetables, nuts, seeds, legumes, and healthy oils are nature’s multi-vitamin and are packed with the nutrients and antioxidants needed to feel, look, and perform your best. These foods help you to reduce your risk of heart disease, stroke, cancer, diabetes, gastro-intestinal problems, high blood pressure and so much more.
The Bottom Line
To keep yourmuscles and bones healthy – here are a few tips:
Choose lean proteins, in moderation, and try to include some vegetarian days in your week. Lean animal proteins include: poultry without the skin, lean cuts of beef with the fat cut off, low fat or fat free dairy, eggs, and fish. Vegetarian proteins include: Beans, tofu, edamame, tempeh, soy milk or other soy products, nuts, nut butters, Seitan, Quorn, quinoa, millet, and amaranth.
Reduce the amount of refined grains in your diet. Focus on snacks being a combination of fruits or vegetables plus a lean protein, rather than a handful of chips, crackers, or other processed snacks. When you do eat grains, choose those that are 100% whole grains such as high fiber/whole grain cereals and breads, brown rice, quinoa, millet, and other complex grains.
At meals times, have vegetables be the star…. and let protein and grains be the side-show.
For Your Bones:
Calcium: Aim for 1,000- 1,200 mg per day
Vitamin D: Aim for 400-1,000 IU per day
Protein: The target in grams is at least half your weight in pounds. {If you weigh175 pounds then the minimum protein you want to aim for is about 87 grams}. Protein needs change depending on your age, exercise level, health, and goals. Some people may need more than this and some people may need less.
Exercise: 30 minutes or more per day! Weight bearing exercise is very important to help keep your bones (and muscles) strong. If you want to stay lean, you need 60-90 minutes per day.
*It is not recommended that you start taking bicarbonate. The goal is to keep your acid-base balance by eating more fruits and vegetables and less grains and protein.
Resources and References:
Nutrition Action, November 2010
Krause’s Food, Nutrition, & Diet Therapy. Mahan, Kathleen; Escott-STump, Sylvia. 11th Edition. 2000.