Even the healthiest people can find it hard to stick with an exercise regimen — and if you suffer from the joint pain of arthritis, moving your body may be the last thing you want to think about. But regular exercise not only helps maintain joint function, but also relieves stiffness and reduces pain and fatigue.

If you have arthritis, you want to be sure your exercise routine has these goals in mind:

1. A better range of motion (improved joint mobility and flexibility). To increase your range of motion, move a joint as far as it can go and then try to push a little farther. These exercises can be done any time, even when your joints are painful or swollen, as long as you do them gently.
2. Stronger muscles (through resistance training). Fancy equipment isn’t needed. You can use your own body weight as resistance to build muscles. For example, the simple exercise described below can help ease the strain on your knees by strengthening your thigh muscles. Sit in a chair. Now lean forward and stand by pushing up with your thigh muscles (use your arms for balance only). Stand a moment, then sit back down, using your thigh muscles.
3. Better endurance. Aerobic exercise — such as walking, swimming, and bicycling — strengthens your heart and lungs and thereby increases endurance and overall health. Stick to activities that don’t jar your joints, and avoid high impact activities such as jogging. If you’re having a flare-up of symptoms, wait until it subsides before doing endurance exercise.
4. Better balance. There are simple ways to work on balance. For example, stand with your weight on both feet. Then try lifting one foot while you balance on the other foot for 5 seconds. Repeat on the other side. Over time, work your way up to 30 seconds. Yoga and tai chi are also good for balance.

Arthritis doesn’t have to keep you from enjoying life.

Our bodies can obtain vitamin D from diet and make it from sun exposure. Even with these two routes for obtaining vitamin D, however, inadequate vitamin D is common, and deficiencies can be found on all continents, in all ethnic groups, and across all ages—a major concern, given the many ways that vitamin D helps protect our health. (1) There are a number of factors that increase the risk of having inadequate vitamin D, among them, lifestyle, sunscreen use, geographic location, skin tone, age, and body weight.

• Lifestyle: People who spend less time outdoors, or who cover up with clothing when they are outdoors, get less exposure to the sun, so they make less vitamin D. (1)
• Sunscreen Use: Correctly-applied sunscreen blocks the harmful ultraviolet B rays that cause skin cancer, but it also blocks most of the skin’s production of vitamin D. So people who use sunscreen daily are more likely to be low in vitamin D. (1) But don’t ditch the sunscreen: The American Academy of Dermatologists says that sunlight exposure to unprotected skin increases the risk of skin cancer, and that there’s no safe level of sunlight exposure that allows you to make vitamin D without increasing skin cancer risk. Their advice? Use sunscreen or other sun protection daily, skip the tanning booths, and get your vitamin D from diet or supplements. (2) Some Vitamin D experts take issue with the American Academy of Dermatologists’ hard line on sun exposure, and they recommend a more moderate option: Put sunscreen on your face, and allow your arms and legs to get a small amount of unprotected sun exposure—say, 15 minutes max—before applying sunscreen or covering up. It’s still a matter of scientific debate.
• Geographic Location and Season: In the summer, if you sat out in a bathing suit on a sunny afternoon for long enough to turn your skin slightly pink, you could make plenty of vitamin D. Yet during the late autumn and winter, people who live at higher latitudes produce little or no vitamin D from the sun, because the sun is at too low an angle in the sky. In the northern hemisphere, people who live in Boston (U.S.), Edmonton (Canada), and Bergen (Norway) can’t make enough vitamin D from the sun for 4, 5, and 6 months out of the year. (3) In the southern hemisphere, residents of Buenos Aires (Argentina) and Cape Town (South Africa) can make far less vitamin D from the sun during their winter months (June through August) than they can during their spring and summer. (3) The body stores vitamin D from summer sun exposure, but it must last for many months. By late winter, many people in these higher-latitude locales are deficient. (1)
• Skin Tone: People who have a darker skin tone have more melanin in their skin, and this pigment is a “natural sunscreen” that slows down skin production of vitamin D. (3)  This the main reason why African Americans are more likely to be low in vitamin D. (4)
• Age: The ability to make vitamin D in the skin drops as we age, and is one of the reasons why older individuals are more likely to have low vitamin D levels. (1)
• Body Weight: People with excess body fat have lower vitamin D levels, so those who are overweight or obese have a higher risk of having inadequate vitamin D.  (1, 5, 6)

The bottom line: Low vitamin D can be found in all ethnic and age groups, around the world, for a host of reasons. Even if you are taking a standard multiple vitamin, the amount of vitamin D in most vitamins (400 IU) is not enough to prevent low blood levels. If you suspect that you are at risk of vitamin D deficiency, you can ask your physician to order a blood test for vitamin D.

Vitamin D Deficiency: A Global Concern

If you live north of the line connecting San Francisco to Philadelphia and Athens to Beijing, odds are that you don’t get enough vitamin D. The same holds true if you don’t get outside for at least a 15-minute daily walk in the sun. African-Americans and others with dark skin, as well as older individuals, tend to have much lower levels of vitamin D, as do people who are overweight or obese.

Worldwide, an estimated 1 billion people have inadequate levels of vitamin D in their blood, and deficiencies can be found in all ethnicities and age groups. (1-3)  Indeed, in industrialized countries, doctors are even seeing the resurgence of rickets, the bone-weakening disease that had been largely eradicated through vitamin D fortification. (4-6)

Why are these widespread vitamin D deficiencies of such great concern? Because research conducted over the past decade suggests that vitamin D plays a much broader disease-fighting role than once thought.

Being “D-ficient” may increase the risk of a host of chronic diseases, such as osteoporosis, heart disease, some cancers, and multiple sclerosis, as well as infectious diseases, such as tuberculosis and even the seasonal flu.

Currently, there’s scientific debate about how much vitamin D people need each day. The Institute of Medicine, in a long-awaited report released on November 30, 2010 recommends tripling the daily vitamin D intake for children and adults in the U.S. and Canada, to 600 IU per day. (7) The report also recognized the safety of vitamin D by increasing the upper limit from 2,000 to 4,000 IU per day, and acknowledged that even at 4,000 IU per day, there was no good evidence of harm. The new guidelines, however, are overly conservative about the recommended intake, and they do not give enough weight to some of the latest science on vitamin D and health. For bone health and chronic disease prevention, many people are likely to need more vitamin D than even these new government guidelines recommend.

Vitamin D Sources and Function

Vitamin D is both a nutrient we eat and a hormone our bodies make. Few foods are naturally rich in vitamin D, so the biggest dietary sources of vitamin D are fortified foods and vitamin supplements. Good sources include dairy products and breakfast cereals (both of which are fortified with vitamin D), and fatty fish such as salmon and tuna.

The body also manufactures vitamin D from cholesterol, through a process triggered by the action of sunlight on skin, hence its nickname, “the sunshine vitamin.”  Yet some people do not make enough vitamin D from the sun, among them, people who have a darker skin tone, who are overweight, who are older, and who cover up when they are in the sun. (1)

Correctly applied sunscreen reduces our ability to absorb vitamin D by more than 90 percent. (8) And not all sunlight is created equal: The sun’s ultraviolet B (UVB) rays—the so-called “tanning” rays, and the rays that trigger the skin to produce vitamin D—are stronger near the equator and weaker at higher latitudes. So in the fall and winter, people who live at higher latitudes (in the northern U.S. and Europe, for example) can’t make much if any vitamin D from the sun. (8)

Vitamin D helps ensure that the body absorbs and retains calcium and phosphorus, both critical for building bone. Laboratory studies show that vitamin D can reduce cancer cell growth and plays a critical role in controlling infections. Many of the body’s organs and tissues have receptors for vitamin D, and scientists are still teasing out its other possible functions.

New Vitamin D Research: Beyond Building Bones

Several promising areas of vitamin D research look far beyond vitamin D’s role in building bones. And, as you might expect, the news media release a flurry of reports every time another study links vitamin D to some new ailment. These reports can be confusing, however, because some studies are stronger than others, and any report needs to be interpreted in the light of all other evidence. More answers may come from randomized trials, such as the VITamin D and OmegA-3 TriaL (VITAL), which will enroll 20,000 healthy men and women to see if taking 2,000 IU of vitamin D or 1,000 mg of fish oil daily lowers the risk of cancer, heart disease, and stroke.

Here, we provide an overview of some of the more promising areas of vitamin D research, highlighting the complex role of vitamin D in disease prevention—and the many unanswered questions that remain.

Vitamin D and Bone and Muscle Strength

Several studies link low vitamin D levels with an increased risk of fractures in older adults, and they suggest that vitamin D supplementation may prevent such fractures—as long as it is taken in a high enough dose. (9-13)

A summary of the evidence comes from a combined analysis of 12 fracture prevention trials that included more than 40,000 elderly people, most of them women. Researchers found that high intakes of vitamin D supplements—of about 800 IU per day—reduced hip and non-spine fractures by 20 percent, while lower intakes (400 IU or less) failed to offer any fracture prevention benefit. (13)

Vitamin D may also help increase muscle strength, which in turn helps to prevent falls, a common problem that leads to substantial disability and death in older people. (14-16)  Once again, vitamin D dose matters: A combined analysis of multiple studies found that taking 700 to 1,000 IU of vitamin D per day lowered the risk of falls by 19 percent, but taking 200 to 600 IU per day did not offer any such protection. (17)

A recent vitamin D trial drew headlines for its unexpected finding that a very high dose of vitamin D increased fracture and fall risk in older women. (18) The trial’s vitamin D dose—500,000 IU taken in a once-a-year pill—was much higher than previously tested in an annual regimen. After up to 5 years of treatment, women in the vitamin D group had a 15 percent higher fall risk and a 26 percent higher fracture risk than women who received the placebo.

It’s possible that giving the vitamin D in one large dose, rather than in several doses spread throughout the year, led to the increased risk. (18) The study authors note that only one other study—also a high-dose, once-a-year regimen—found vitamin D to increase fracture risk; no other studies have found vitamin D to increase the risk of falls. Furthermore, there’s strong evidence that more moderate doses of vitamin D taken daily or weekly protect against fractures and falls—and are safe.

So what is the significance of this study for people who want to take vitamin D supplements? A reasonable conclusion would be to continue taking moderate doses of vitamin D regularly, since these have a strong safety record, but to avoid extremely high single doses. This recent finding does present a challenge to scientists who will work to understand why the extreme single dose appears to have adverse effects.

Vitamin D and Heart Disease

The heart is basically a large muscle, and like skeletal muscle, it has receptors for vitamin D. (19) So perhaps it’s no surprise that studies are finding vitamin D deficiency may be linked to heart disease. The Health Professional Follow-Up Study checked the vitamin D blood levels in nearly 50,000 men who were healthy, and then followed them for 10 years. (20) They found that men who were deficient in vitamin D were twice as likely to have a heart attack as men who had adequate levels of vitamin D. Other studies have found that low vitamin D levels were associated with higher risk of heart failure, sudden cardiac death, stroke, overall cardiovascular disease, and cardiovascular death. (21-24) How exactly might vitamin D help prevent heart disease? There’s evidence that vitamin D plays a role in controlling blood pressure and preventing artery damage, and this may explain these findings. (25) Still, more research is needed before we can be confident of these benefits.

Vitamin D and Cancer

Nearly 30 years ago, researchers noticed an intriguing relationship between colon cancer deaths and geographic location: People who lived at higher latitudes, such as in the northern U.S., had higher rates of death from colon cancer than people who live closer to the equator. (26) Many scientific hypotheses about vitamin D and disease stem from studies that have compared solar radiation and disease rates in different countries. These can be a good starting point for other research but don’t provide the most definitive information. The sun’s UVB rays are weaker at higher latitudes, and in turn, people’s vitamin D levels in these high latitude locales tend to be lower. This led to the hypothesis that low vitamin D levels might somehow increase colon cancer risk. (2)

Since then, dozens of studies suggest an association between low vitamin D levels and increased risks of colon and other cancers. (1,27)  The evidence is strongest for colorectal cancer, with most (but not all) observational studies finding that the lower the vitamin D levels, the higher the risk of these diseases. (28-38) Vitamin D levels may also predict cancer survival, but evidence for this is still limited. (27) Yet finding such associations does not necessarily mean that taking vitamin D supplements will lower cancer risk.

The VITAL trial will look specifically at whether vitamin D supplements lower cancer risk. It will be years, though, before it releases any results. It could also fail to detect a real benefit of vitamin D, for several reasons: If people in the placebo group decide on their own to take vitamin D supplements, that could minimize any differences between the placebo group and the supplement group; the study may not follow participants for a long enough time to show a cancer prevention benefit; or study participants may be starting supplements too late in life to lower their cancer risk. In the meantime, based on the evidence to date, 16 scientists have circulated a “call for action” on vitamin D and cancer prevention: (27) Given the high rates of vitamin D deficiency in North America, the strong evidence for reduction of osteoporosis and fractures, the potential cancer-fighting benefits of vitamin D, and the low risk of vitamin D supplementation, they recommend widespread vitamin D supplementation of 2000 IU per day. (27)

Vitamin D and Immune Function

Vitamin D’s role in regulating the immune system has led scientists to explore two parallel research paths: Does vitamin D deficiency contribute to the development of multiple sclerosis, type 1 diabetes, and other so-called “autoimmune” diseases, where the body’s immune system attacks its own organs and tissues? And could vitamin D supplements help boost our body’s defenses to fight infectious disease, such as tuberculosis and seasonal flu? This is a hot research area and more findings will be emerging.

Vitamin D and Multiple Sclerosis: Multiple sclerosis (MS) rates are much higher far north (or far south) of the equator than in sunnier climes, and researchers suspect that chronic vitamin D deficiencies may be one reason why. One prospective study to look at this question found that among white men and women, those with the highest vitamin D blood levels had a 62 percent lower risk of developing MS than those with the lowest vitamin D levels. (39) The study didn’t find this effect among black men and women, most likely because there were fewer black study participants and most of them had low vitamin D levels, making it harder to find any link between vitamin D and MS if one exists.

Vitamin D and Type 1 Diabetes: Type 1 diabetes is another disease that varies with geography—a child in Finland is about 400 times more likely to develop it than a child in Venezuela. (40) Evidence that vitamin D may play a role in preventing type 1 diabetes comes from a 30-year study that followed more than 10,000 Finnish children from birth: Children who regularly received vitamin D supplements during infancy had a nearly 90 percent lower risk of developing type 1 diabetes than those who did not receive supplements. (41)  Other European case-control studies, when analyzed together, also suggest that vitamin D may help protect against type 1 diabetes. (42) No randomized controlled trials have tested this notion, and it is not clear that they would be possible to conduct.

Vitamin D, the Flu, and the Common Cold: The flu virus wreaks the most havoc in the winter, abating in the summer months. This seasonality led a British doctor to hypothesize that a sunlight-related “seasonal stimulus” triggered influenza outbreaks. (43) More than 20 years after this initial hypothesis, several scientists published a paper suggesting that vitamin D may be the seasonal stimulus. (44) Among the evidence they cite:

• Vitamin D levels are lowest in the winter months. (44) 
• The active form of vitamin D tempers the damaging inflammatory response of some white blood cells, while it also boosts immune cells’ production of microbe-fighting proteins. (44) 
• Children who have vitamin D-deficiency rickets are more likely to get respiratory infections, while children exposed to sunlight seem to have fewer respiratory infections. (44) 
• Adults who have low vitamin D levels are more likely to report having had a recent cough, cold, or upper respiratory tract infection. (45)

A recent randomized controlled trial in Japanese school children tested whether taking daily vitamin D supplements would prevent seasonal flu. (46) The trial followed nearly 340 children for four months during the height of the winter flu season. Half of the study participants received pills that contained 1,200 IU of vitamin D; the other half received placebo pills. Researchers found that type A influenza rates in the vitamin D group were about 40 percent lower than in the placebo group; there was no significant difference in type B influenza rates. This was a small but promising study, and more research is needed before we can definitively say that vitamin D protects against the flu. But don’t skip your flu shot, even if vitamin D has some benefit.

Vitamin D and Tuberculosis: Before the advent of antibiotics, sunlight and sun lamps were part of the standard treatment for tuberculosis (TB). (47) More recent research suggests that the “sunshine vitamin” may be linked to TB risk. Several case-control studies, when analyzed together, suggest that people diagnosed with tuberculosis have lower vitamin D levels than healthy people of similar age and other characteristics. (48)   Such studies do not follow individuals over time, so they cannot tell us whether vitamin D deficiency led to the increased TB risk or whether taking vitamin D supplements would prevent TB. There are also genetic differences in the receptor that binds vitamin D, and these differences may influence TB risk. (49) Again, more research is needed. (49)

Vitamin D and Risk of Premature Death

A promising report in the Archives of Internal Medicine suggests that taking vitamin D supplements may even reduce overall mortality rates: A combined analysis of multiple studies found that taking modest levels of vitamin D supplements was associated with a statistically significant 7 percent reduction in mortality from any cause. (50) The analysis looked at the findings from 18 randomized controlled trials that enrolled a total of nearly 60,000 study participants; most of the study participants took between 400 and 800 IU of vitamin D per day for an average of five years. Keep in mind that this analysis has several limitations, chief among them the fact that the studies it included were not designed to explore mortality in general, or explore specific causes of death. More research is needed before any broad claims can be made about vitamin D and mortality. (51)

Osteoporosis means ‘bones with holes’. Bones lose their strength and density, become fragile and break (fracture) more easily because of calcium loss. Breaks are most common in the spine, hip and wrist and often occur after only a minor fall or knock. Osteoporosis particularly affects women in their middle and later years, although some men are also affected.

Most people show no signs of developing osteoporosis until a fracture occurs. Both men and women can take steps from a young age to avoid developing the condition in later life. Reduce your risk of fractures by taking steps to prevent and treat osteoporosis (or brittle bones) and avoid falls wherever possible. Activity and a healthy diet rich in calcium and vitamin D are both important.

Osteoporosis and bone growth
Bone is formed by specialised cells. Like the rest of the body, bone is constantly being broken down and renewed. It is living tissue that needs exercise to gain strength, just like muscle. In the early years of life, more bone is made than is broken down, resulting in bone growth. By the end of your teens, bone growth has been completed and ‘peak bone mass’ is achieved.

Sex hormones, such as oestrogen and testosterone, have a fundamental role in maintaining bone strength in men and women. The fall in oestrogen blood levels that occurs during menopause results in accelerated bone loss. During the first five years after menopause, the average woman loses up to 10 per cent of her total body bone.

Fractures of the spine caused by osteoporosis can lead to loss of height, pain and changes in posture such as the ‘Dowager’s hump’. This hump is caused when spinal fractures are compressed due to the force of gravity, resulting in an abnormal bending of the spine (kyphosis).

Symptoms
Osteoporosis causes no specific pain or symptoms. However, it does increase the risk of serious or debilitating fractures. If you think you may be at risk of developing osteoporosis, see your doctor.

Risk factors for osteoporosis
Several factors can place a person at risk of osteoporosis. Risk factors include:

• Family history of osteoporosis (mother, sister or grandmother)

• Inadequate amounts of dietary calcium

• Low vitamin D levels

• Cigarette smoking

• Alcohol intake of more than two standard drinks per day

• Caffeine intake of more than three cups of tea, coffee or equivalent per day

• Lack of physical activity

• Early menopause before the age of 45

• Loss of menstrual period if it is associated with reduced production of oestrogen, which is vital for healthy bones (the menstrual cycle can cease following excessive dieting and exercise)

• Long-term use of medications such as corticosteroids for rheumatoid arthritis and asthma.

Some conditions place people at a higher risk of osteoporosis. These conditions include:

• Thyroid disease or an over active thyroid gland

• Rheumatoid arthritis

• Chronic liver and kidney disease

• Conditions that affect the body’s ability to absorb nutrients, such as Crown’s disease, coeliac disease and other inflammatory bowel conditions.

Preventing osteoporosis
Both men and women can take steps from a young age to prevent osteoporosis by making sure that they:

• Have a healthy and varied diet with plenty of fresh fruit, vegetables and whole grains

• Eat calcium rich foods

• Absorb enough Vitamin D

• Avoid smoking

• Limit alcohol consumption

• Limit caffeine

• Do regular weight bearing and strength training activities.

A varied and calcium rich diet is the key
We need calcium to build and maintain strong and healthy bones, help our muscles work and support our nervous system. Good sources of calcium include:

• Dairy foods – low fat varieties are available to reduce the risk of weight gain or raised cholesterol levels

• Canned fish with edible bones – for example, sardines.

The minimum recommended daily intake of dietary calcium is:

• Infants (under 12 months) – 210–270mg calcium per day

• Children (over four years) – 700–1,000mg calcium per day

• Adolescents – 1,300mg calcium per day

• Women under 50 and men under 70 – 1,000mg calcium per day

• Post menopausal women and men over 70 – 1,300mg calcium per day.

Adequate vitamin D
Vitamin D levels are increased with sun exposure. People who are housebound or who dress with most of their body covered are at risk of vitamin D deficiency. The majority of women have inadequate levels of vitamin D during winter months. All that is needed is 10–20 minutes of sun exposure to the arms and face daily, without sunscreen and not through glass. Sun exposure is safest before 11am or after 3pm.

Avoid smoking
Evidence has shown that smokers have a lower bone density. Nicotine is known to be toxic to bone cells.

Limit alcohol intake
Excessive alcohol consumption is associated with the development of osteoporosis. Restrict your alcohol intake to no more than two standard drinks on any one day for both men and women to reduce your risk. Everyone should have at least two alcohol-free days each week.

Reduce caffeine intake
A large amount of caffeine (more than two to three cups per day of cola, tea or coffee) has also been associated with an increased risk of osteoporosis.

Do regular weight bearing and strength training activities
You should exercise at least 30 minutes three to four times a week to maintain healthy bones. Recommended activities are:

• Walking

• Jogging

• Tennis

• Dancing

• Using weights.

This helps maintain bone strength and balance so falls are reduced.

Diagnosis
The most reliable way to diagnose osteoporosis is to measure bone density using a DEXA scan. This is done with x-ray technology that involves minimal radiation, is accurate and can be used to follow up treatment.

Ultrasound tests are available at many pharmacies and involve an ultrasound measurement of the heel. These tests are not as accurate in assessing for osteoporosis as a DEXA study and are not recommended by doctors.

It’s never too late for treatment
If you have osteoporosis, it is never too late to seek treatment. Treatment can halt bone loss and significantly reduce the risk of fractures. It is important that your doctor excludes other medical conditions that can cause osteoporosis, including vitamin D deficiency.

Medications and treatments are available to strengthen bones and prevent fractures by slowing down bone loss. They may improve bone density in women with osteoporosis after the menopause.

Available medical treatments include:

• Bisphosphonates – such as alendronate, risedronate and zolindrinic acid, which can be combined with vitamin D and calcium

• Strontium ranelate – also called Protelos

• Selective oestrogen receptor modulators (SERMs) – in the form of raloxifene

• Vitamin D derivatives and calcium supplements

• Hormone replacement therapy (HRT) – short-term use of oestrogen and progestogen at menopause.

Other potential therapies that may be used as treatment include parathyroid hormone.

Hormone replacement therapy
All treatments for osteoporosis aim to prevent fractures. Oestrogen replacement at menopause prevents bone loss and fractures, but the effect lasts only as long as oestrogen is used.

Oestrogen can be is used to prevent fractures mainly for younger women with premature menopause. This is because most fractures do not occur until after the age of 65 and long-term oestrogen use is not recommended.

Falls are a risk for people with osteoporosis
For people with osteoporosis, even minor trauma – such as coughing, knocks on the limbs and simple falls – can lead to fractures. Falls are a particular problem in the elderly as they are often more likely to result in fractures, particularly of the hip. Any fracture occurring from minimal trauma should be investigated as it may indicate underlying osteoporosis.

There are several ways to reduce your risk of falls. It may be necessary to see a physiotherapist and/or occupational therapist to provide assistance with walking aides and ensure your home environment is safe. Talk with your doctor or contact your community health centre to find the services you need.

Things to remember

• Osteoporosis occurs when bones lose their density and strength.

• A healthy lifestyle throughout life (adequate dietary calcium and regular physical activity) can help prevent osteoporosis.

• Oestrogen replacement helps maintain bone density in women with premature menopause.