How to Boost Your PIDD Bone Health

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How to Boost Your PIDD Bone Health: A Definitive Guide

For individuals living with Primary Immunodeficiency Diseases (PIDD), bone health is not merely a secondary concern; it’s a critical pillar of overall well-being. PIDD, a group of more than 450 chronic genetic disorders that impair the immune system, often brings with it a higher risk of bone complications, including osteopenia, osteoporosis, and fractures. The chronic inflammation inherent in many PIDDs, the long-term use of certain medications, and nutritional challenges can all contribute to this increased vulnerability. This guide delves deep into the actionable strategies and essential knowledge required to proactively safeguard and strengthen your bone health when living with PIDD. It’s a roadmap designed to empower you with the tools to build a resilient skeletal system, mitigate risks, and enhance your quality of life.

Understanding the intricate relationship between PIDD and bone health is the first step. The immune system and skeletal system are far more interconnected than previously thought, with immune cells playing a direct role in bone remodeling – the continuous process of old bone breakdown and new bone formation. When this delicate balance is disrupted by chronic inflammation or immune dysregulation, bone health inevitably suffers. This guide will move beyond the superficial, offering concrete, evidence-informed approaches to fortify your bones, from tailored nutritional strategies to targeted exercise regimens and crucial medical considerations.

Unraveling the PIDD-Bone Health Connection: Why Are You More Vulnerable?

Before we dive into solutions, it’s vital to grasp the specific mechanisms that link PIDD to compromised bone health. This understanding will underscore the importance of each intervention and help you prioritize your efforts.

The Impact of Chronic Inflammation

Many PIDDs are characterized by persistent, low-grade, or intermittent inflammation. This chronic inflammatory state is a major antagonist to bone health. Inflammatory cytokines, signaling molecules released by immune cells, can directly stimulate osteoclasts (cells responsible for bone breakdown) and inhibit osteoblasts (cells responsible for bone formation). This skewed balance leads to accelerated bone loss.

  • Concrete Example: In patients with Common Variable Immunodeficiency (CVID), a frequent PIDD, chronic lung infections and gut inflammation are common. These localized inflammatory processes can trigger a systemic inflammatory response, releasing pro-inflammatory cytokines like TNF-α, IL-1, and IL-6. These cytokines directly promote osteoclast activity and suppress osteoblast function, leading to a net loss of bone mineral density over time. Imagine these cytokines as tiny wrecking balls constantly chipping away at your bone structure without adequate repair.

Medication-Induced Bone Loss

Certain medications critical for managing PIDD can unfortunately have detrimental effects on bone density. Corticosteroids are perhaps the most well-known culprits.

  • Concrete Example: Long-term use of oral corticosteroids (e.g., prednisone) for conditions like autoimmune manifestations associated with PIDD can significantly accelerate bone loss. Corticosteroids decrease calcium absorption from the gut, increase calcium excretion by the kidneys, and directly inhibit osteoblast function while promoting osteoclast activity. A patient on daily prednisone for several months might experience a rapid decline in bone density, making fracture prevention a paramount concern. This is why physicians meticulously weigh the benefits against the risks and strive for the lowest effective dose and shortest duration possible.

Nutritional Deficiencies and Malabsorption

Some PIDDs, particularly those affecting the gastrointestinal tract (e.g., specific forms of Severe Combined Immunodeficiency or certain CVID phenotypes), can lead to malabsorption of vital nutrients essential for bone health.

  • Concrete Example: A patient with chronic diarrhea due to a PIDD-related enteropathy might struggle to absorb fat-soluble vitamins, including Vitamin D, even if their dietary intake is adequate. Vitamin D is crucial for calcium absorption. Without sufficient Vitamin D, even a calcium-rich diet won’t fully translate into strong bones. This can lead to a vicious cycle where poor gut health directly compromises bone integrity.

Reduced Physical Activity and Chronic Illness

Living with a chronic illness like PIDD can sometimes lead to reduced physical activity due to fatigue, frequent infections, or other symptoms. Weight-bearing exercise is a powerful stimulus for bone formation.

  • Concrete Example: A child with a PIDD who experiences recurrent infections and prolonged hospital stays may spend more time sedentary. This lack of weight-bearing activity means their bones are not receiving the necessary mechanical stress to stimulate osteoblast activity. Over time, this can result in lower peak bone mass compared to their healthy peers, setting them up for increased fracture risk later in life.

Direct Immune System-Bone Cell Interactions

Beyond inflammation, the immune system directly communicates with bone cells. Dysregulation in this communication pathway, inherent in PIDD, can impact bone remodeling.

  • Concrete Example: Certain immune cells, like T-lymphocytes, can directly produce factors that influence osteoclast and osteoblast activity. In some PIDDs, an imbalance in T-cell subsets or their cytokine production can inadvertently tip the scales towards bone resorption, even in the absence of overt inflammation. It’s like having the “on” switch for bone breakdown stuck in the “on” position without a counterbalance.

Fortifying Your Foundation: Nutritional Strategies for Bone Resilience

Nutrition is the bedrock of bone health. For individuals with PIDD, a proactive and meticulously planned nutritional approach is not just beneficial, but essential. This goes beyond simply “eating healthy”; it involves strategic choices and, often, targeted supplementation under medical guidance.

Calcium: The Building Block

Calcium is the primary mineral component of bone. Ensuring adequate intake is non-negotiable, but the source and absorption are equally critical.

  • Actionable Explanation: Aim for 1000-1200 mg of calcium daily for most adults, though specific needs can vary based on age, gender, and PIDD type. While dairy products are renowned sources, explore diverse options, especially if you have lactose intolerance or dietary restrictions.

  • Concrete Example: Instead of solely relying on milk, incorporate fortified plant-based milks (almond, soy, oat), leafy green vegetables like kale and collard greens, fortified cereals, and calcium-set tofu. For instance, 1 cup of fortified almond milk can provide 450 mg of calcium, while 1 cup of cooked collard greens offers around 260 mg. If dietary intake is consistently insufficient, a calcium supplement (e.g., calcium carbonate or citrate) might be recommended by your doctor, ideally taken in divided doses (e.g., 500 mg twice daily) to optimize absorption. Avoid taking large doses at once, as absorption efficiency decreases.

Vitamin D: The Calcium Conductor

Vitamin D is not merely a vitamin; it acts as a hormone that regulates calcium and phosphate metabolism, crucial for bone mineralization. Without adequate Vitamin D, calcium absorption from the gut is severely compromised.

  • Actionable Explanation: Sunlight exposure is a primary source, but due to varying factors like geography, skin type, and the risk of sun damage, especially for some PIDD patients, dietary sources and supplementation are often necessary.

  • Concrete Example: Fatty fish (salmon, mackerel, sardines), fortified dairy products, and fortified orange juice are good dietary sources. However, it’s often challenging to meet requirements solely through diet. Blood tests for 25-hydroxyvitamin D levels are crucial to determine your baseline and guide supplementation. Many PIDD patients require higher doses than the general population due to malabsorption or chronic inflammation. Your doctor might recommend 1000-5000 IU of Vitamin D3 daily, or even higher initial loading doses if you are severely deficient. A good example is a patient whose labs show a Vitamin D level of 15 ng/mL (deficient), who might be prescribed 50,000 IU of Vitamin D3 once weekly for 8 weeks, followed by a maintenance dose of 2000-4000 IU daily.

Magnesium: The Co-Factor

Magnesium plays a vital role in bone structure and influences calcium and Vitamin D metabolism. It’s often overlooked but critically important.

  • Actionable Explanation: Aim for 310-420 mg of magnesium daily for adults.

  • Concrete Example: Incorporate nuts (almonds, cashews), seeds (pumpkin, chia), legumes (black beans, lentils), whole grains (quinoa, brown rice), and dark leafy greens (spinach, Swiss chard). A small handful of almonds (about 1 ounce) provides 80 mg of magnesium, while a cup of cooked spinach offers about 157 mg. If a supplement is needed, magnesium citrate or glycinate are generally well-absorbed forms.

Vitamin K2: Directing Calcium Traffic

Often overshadowed by Vitamin D, Vitamin K2 is gaining recognition for its role in bone health by directing calcium to the bones and away from soft tissues where it could cause calcification.

  • Actionable Explanation: While official recommendations are still evolving, including Vitamin K2-rich foods is a proactive step.

  • Concrete Example: Natto (fermented soybeans) is an exceptionally rich source of MK-7, a highly bioavailable form of Vitamin K2. Other sources include certain cheeses (Gouda, Brie), egg yolks, and organ meats. While most people get some K1 from leafy greens, K2 is less common in Western diets. A small serving of natto (1-2 tablespoons) can provide hundreds of micrograms of K2.

Protein: The Bone Matrix Builder

Bone is not just mineral; it’s a complex matrix, largely composed of protein (collagen). Adequate protein intake is essential for building and repairing this matrix.

  • Actionable Explanation: Ensure you’re consuming sufficient high-quality protein throughout the day.

  • Concrete Example: Include lean meats, poultry, fish, eggs, dairy, legumes, and plant-based protein sources like quinoa and tofu. Aim for about 0.8-1.0 grams of protein per kilogram of body weight, distributed across meals. For instance, a 70 kg individual would aim for 56-70 grams of protein daily. A 3-ounce serving of chicken breast provides about 25 grams of protein, and a cup of lentils offers 18 grams.

Probiotics and Gut Health: An Indirect Link

Given that some PIDDs affect gut integrity and nutrient absorption, supporting gut health through probiotics can indirectly benefit bone health by optimizing nutrient uptake.

  • Actionable Explanation: Consider incorporating probiotic-rich foods or a targeted probiotic supplement.

  • Concrete Example: Fermented foods like yogurt (with live active cultures), kefir, sauerkraut, and kimchi can introduce beneficial bacteria to your gut. If considering a supplement, consult your doctor to choose a strain appropriate for your specific PIDD and any associated gut issues. For a patient with PIDD-related enteropathy, improving gut microbiota balance might enhance the absorption of fat-soluble vitamins like Vitamin D.

Moving for Bone Strength: Tailored Exercise for PIDD Patients

Exercise is a potent osteogenic (bone-building) stimulus. For individuals with PIDD, the type, intensity, and consistency of exercise must be carefully considered, taking into account individual health status, fatigue levels, and infection risk. The goal is to maximize bone benefits while minimizing risks.

Weight-Bearing Exercise: The Bone Stimulus

Weight-bearing exercises are those where your bones and muscles work against gravity. This stress signals osteoblasts to lay down new bone tissue.

  • Actionable Explanation: Incorporate activities that place healthy stress on your bones. Start gradually and increase intensity as tolerated.

  • Concrete Example:

    • Walking: Even a brisk 30-minute walk, 3-5 times a week, can be highly effective. If you’re new to exercise or prone to fatigue, begin with 10-15 minute walks and gradually extend the duration. Walk around your neighborhood, in a park, or on a treadmill.

    • Dancing: A fun and engaging way to get weight-bearing exercise. Join a dance class, or simply put on music and dance at home. This also improves balance and coordination.

    • Stair Climbing: Opt for stairs instead of elevators when possible. Even a few flights daily add up.

    • Low-Impact Aerobics: If higher impact is too much, consider classes like step aerobics or specific low-impact routines that still put healthy stress on bones.

    • Hiking: If your energy permits, hiking on varied terrain provides excellent weight-bearing challenge.

Resistance Training: Building Muscle, Building Bone

Resistance (or strength) training involves working your muscles against a force, which in turn pulls on your bones, stimulating bone growth and increasing bone density. It also builds muscle mass, which protects bones and improves balance, reducing fall risk.

  • Actionable Explanation: Use body weight, resistance bands, free weights, or weight machines. Aim for 2-3 sessions per week, targeting all major muscle groups.

  • Concrete Example:

    • Bodyweight Exercises: Squats, lunges, push-ups (modified on knees if needed), planks, and wall sits. For instance, perform 3 sets of 10-12 repetitions of wall squats daily.

    • Resistance Bands: Can be used for arm curls, shoulder presses, leg presses, and rows. They are versatile and provide progressive resistance.

    • Light Weights: Hand weights or ankle weights can be used for bicep curls, triceps extensions, overhead presses, and leg raises. Start with 1-2 lb weights and gradually increase as you get stronger.

    • Supervised Programs: If possible, work with a physical therapist or exercise physiologist who understands PIDD to develop a safe and effective resistance training program tailored to your specific needs and limitations. They can guide you on proper form to prevent injuries. For example, a physical therapist might design a program focusing on strengthening core muscles and quadriceps to improve stability and reduce fall risk, which indirectly protects bones.

Balance and Flexibility: Preventing Falls, Preventing Fractures

Falls are a major cause of fractures, particularly in individuals with compromised bone density. Improving balance and flexibility can significantly reduce this risk.

  • Actionable Explanation: Incorporate activities that challenge your balance and improve your range of motion.

  • Concrete Example:

    • Tai Chi or Yoga: These practices are excellent for improving balance, flexibility, and core strength, often with a low impact on joints. Many studios offer beginner or chair yoga classes that can be adapted. A 45-minute Tai Chi session twice a week can significantly improve balance and reduce fall risk.

    • Single-Leg Stands: Practice standing on one leg for 30 seconds at a time, holding onto a stable surface initially for support. Gradually increase the duration and remove support.

    • Heel-to-Toe Walking: Walk with the heel of one foot directly in front of the toes of the other, like walking on a tightrope.

    • Stretching: Gentle stretching routines improve flexibility and can alleviate muscle stiffness that might contribute to imbalance. Focus on major muscle groups, holding each stretch for 20-30 seconds.

Key Considerations for Exercise with PIDD:

  • Listen to Your Body: Fatigue and illness are common in PIDD. It’s crucial to know when to rest and when to push gently. Don’t exercise when you’re feeling unwell or during an acute infection.

  • Consult Your Healthcare Team: Before starting any new exercise program, especially if you have specific physical limitations or co-existing conditions, consult your immunologist, physical therapist, or other healthcare providers. They can provide personalized recommendations and ensure safety.

  • Start Slow and Progress Gradually: Don’t try to do too much too soon. Consistency over intensity is key, especially in the beginning. Gradually increase duration, frequency, or intensity as your strength and stamina improve.

  • Hydration: Stay well-hydrated before, during, and after exercise.

  • Appropriate Footwear: Wear supportive, well-cushioned shoes, especially for weight-bearing activities, to protect your joints and provide stability.

Medical Management and Monitoring: Your Doctor’s Role

Beyond lifestyle interventions, proactive medical management and close monitoring are critical components of PIDD bone health strategy. Your healthcare team plays a pivotal role in identifying risks, assessing bone density, and recommending targeted treatments.

Regular Bone Density Screenings (DEXA Scans)

Dual-energy X-ray absorptiometry (DEXA) scans are the gold standard for measuring bone mineral density (BMD) and diagnosing osteopenia or osteoporosis.

  • Actionable Explanation: Your immunologist or endocrinologist should determine the appropriate frequency of DEXA scans based on your PIDD type, medication history (especially corticosteroid use), and other risk factors.

  • Concrete Example: For a PIDD patient on long-term corticosteroids, a baseline DEXA scan might be performed, followed by subsequent scans every 1-2 years to monitor changes in BMD and assess the effectiveness of interventions. If a patient is diagnosed with osteopenia, a repeat scan might be scheduled sooner to track progression or improvement.

Blood Tests for Bone Markers and Nutrient Levels

Beyond Vitamin D, several other blood tests can provide valuable insights into your bone health status.

  • Actionable Explanation: Regular monitoring of these markers helps identify deficiencies and assess bone turnover.

  • Concrete Example:

    • Serum Calcium and Phosphate: To assess overall mineral balance.

    • Parathyroid Hormone (PTH): Elevated PTH can indicate Vitamin D deficiency or other issues impacting calcium regulation.

    • Alkaline Phosphatase (ALP): A general marker of bone formation, though it can be elevated in other conditions too.

    • Bone Turnover Markers: Specific markers like CTx (C-telopeptide, indicating bone resorption) and P1NP (procollagen type 1 N-terminal propeptide, indicating bone formation) can provide a more dynamic picture of bone remodeling, especially useful for monitoring treatment effectiveness. Your doctor might order these if there’s concern about rapid bone loss. For example, a PIDD patient with a persistently high CTx level, even with adequate calcium and vitamin D, might indicate ongoing high bone turnover that requires further investigation.

Medication Review and Optimization

Working with your doctor to minimize the bone-damaging effects of necessary medications is crucial.

  • Actionable Explanation: Discuss alternatives or strategies to mitigate bone loss if you are on medications known to affect bone density.

  • Concrete Example: If you are on high-dose corticosteroids, your doctor might explore steroid-sparing agents or attempt to taper the dose as much as clinically possible. They may also prescribe specific bone-protective medications concurrently. For example, a PIDD patient requiring long-term prednisone might be co-prescribed a bisphosphonate (e.g., alendronate) or denosumab to counteract steroid-induced bone loss.

Pharmacological Interventions for Osteoporosis

If osteopenia progresses to osteoporosis or if fracture risk is very high, specific medications may be necessary to increase bone density and reduce fracture risk.

  • Actionable Explanation: These medications work through various mechanisms to either slow bone breakdown or stimulate bone formation.

  • Concrete Example:

    • Bisphosphonates (e.g., Alendronate, Risedronate, Zoledronic Acid): These are the most commonly prescribed medications. They work by inhibiting osteoclast activity, thereby slowing bone resorption. An example is a weekly oral alendronate tablet, which helps maintain or increase BMD in the spine and hip.

    • Denosumab (Prolia): An injectable medication given every six months, Denosumab is a monoclonal antibody that targets RANKL, a protein essential for osteoclast formation and function. It’s often considered for patients who can’t tolerate bisphosphonates or have more severe bone loss.

    • Teriparatide (Forteo) and Abaloparatide (Tymlos): These are anabolic (bone-building) agents that stimulate new bone formation, reserved for severe osteoporosis or very high fracture risk, often given daily via injection for a limited time (e.g., 18-24 months).

    • Romosozumab (Evenity): A newer anabolic agent that both increases bone formation and decreases bone resorption, given monthly via injection for a limited time (12 months).

The choice of medication will depend on your specific PIDD, co-existing conditions, fracture history, and a thorough discussion with your doctor about potential side effects and benefits.

Lifestyle Adjustments and Environmental Safety: Beyond the Basics

While nutrition, exercise, and medical management form the core, several lifestyle adjustments and environmental considerations can further bolster your bone health and significantly reduce the risk of fractures.

Fall Prevention: A Proactive Stance

Fractures often occur due to falls. For PIDD patients, who might experience muscle weakness, fatigue, or balance issues, fall prevention is paramount.

  • Actionable Explanation: Identify and mitigate fall hazards in your home and environment.

  • Concrete Example:

    • Home Safety Check: Remove tripping hazards like loose rugs, clutter on floors, and electrical cords. Ensure adequate lighting in all areas, especially stairways and hallways. Install grab bars in bathrooms near the toilet and in the shower/tub. Use non-slip mats in wet areas.

    • Footwear: Wear supportive, non-slip shoes with good traction, both indoors and outdoors. Avoid walking in socks or flimsy slippers that offer no support.

    • Vision Check: Regular eye exams are crucial. Corrected vision reduces the risk of missteps.

    • Medication Review: Discuss with your doctor or pharmacist if any of your medications cause dizziness, drowsiness, or affect balance, and explore alternatives or timing adjustments.

    • Assistive Devices: If necessary, use a cane or walker, as recommended by a physical therapist, to improve stability and confidence.

Smoking Cessation and Alcohol Moderation: Harmful Habits

Smoking and excessive alcohol consumption are well-established risk factors for poor bone health.

  • Actionable Explanation: Eliminate smoking entirely and moderate alcohol intake.

  • Concrete Example:

    • Smoking: Nicotine and other toxins in cigarettes directly inhibit osteoblasts and impair calcium absorption. Quitting smoking can slow down bone loss and improve overall health. Seek support from your healthcare team, cessation programs, or nicotine replacement therapy.

    • Alcohol: Excessive alcohol consumption interferes with calcium and Vitamin D absorption, impairs osteoblast function, and can increase fall risk. Limit alcohol to no more than one drink per day for women and two for men, or ideally, abstain if possible.

Managing Chronic Pain and Fatigue: Indirect Bone Benefits

Chronic pain and fatigue, common in PIDD, can limit physical activity and impact overall well-being, indirectly affecting bone health.

  • Actionable Explanation: Work with your healthcare team to effectively manage pain and fatigue, allowing for greater engagement in bone-healthy activities.

  • Concrete Example:

    • Pain Management: Explore various strategies such as physical therapy, gentle exercise, medication adjustments, or complementary therapies (e.g., acupuncture, massage) to reduce pain. Less pain means more mobility.

    • Fatigue Management: Implement energy-conservation techniques, prioritize rest, and discuss potential underlying causes with your doctor. Regular, moderate exercise can paradoxically help improve energy levels over time.

Stress Management: A Holistic Approach

Chronic stress can influence hormone levels (e.g., cortisol), which in turn can negatively impact bone metabolism.

  • Actionable Explanation: Incorporate stress-reduction techniques into your daily routine.

  • Concrete Example: Practice mindfulness meditation, deep breathing exercises, spend time in nature, engage in hobbies, or connect with supportive friends and family. Even 10-15 minutes of quiet reflection or light stretching can make a difference in reducing stress hormones.

The Power of a Multidisciplinary Team: Collaboration for Optimal Outcomes

Optimizing bone health in PIDD is rarely a solitary endeavor. It requires the coordinated efforts of a multidisciplinary healthcare team, each specialist contributing their unique expertise.

Your Immunologist: The Central Coordinator

Your immunologist is the primary specialist managing your PIDD and typically coordinates your overall care.

  • Role: They understand the specific immunological aspects of your condition that impact bone health, manage immune globulin replacement therapy, and adjust immunosuppressants or other medications that might affect bones. They are crucial for initiating bone density screenings and referrals.

  • Actionable Interaction: Discuss your bone health concerns directly with your immunologist. Ask about recommended screening frequencies, potential medication side effects on bones, and referrals to other specialists.

Endocrinologist: The Bone Metabolism Expert

An endocrinologist specializes in hormones and metabolic bone diseases.

  • Role: They can provide in-depth assessment and management of osteoporosis, Vitamin D deficiency, and other hormonal imbalances affecting bone. They are experts in prescribing and monitoring bone-specific medications.

  • Actionable Interaction: If your DEXA scan reveals significant osteopenia or osteoporosis, or if you have complex metabolic bone issues, your immunologist will likely refer you to an endocrinologist for specialized care. Be prepared to discuss your PIDD history, medications, and any other relevant medical conditions.

Registered Dietitian/Nutritionist: The Food Strategist

A dietitian specializing in chronic illness or immunology can provide tailored nutritional guidance.

  • Role: They can assess your dietary intake, identify potential deficiencies, address malabsorption issues, and create a personalized meal plan to optimize calcium, Vitamin D, and other essential nutrient intake, considering any food allergies or intolerances related to your PIDD.

  • Actionable Interaction: Ask your immunologist for a referral to a dietitian. Work with them to create a realistic and enjoyable eating plan that supports both your bone health and overall PIDD management. For instance, they might suggest specific nutrient-dense foods that are well-tolerated if you have gut issues.

Physical Therapist: The Movement Specialist

A physical therapist (PT) is essential for developing safe and effective exercise programs.

  • Role: They can assess your strength, balance, posture, and mobility. They can design personalized weight-bearing and resistance exercises, teach proper form, and help you improve balance and reduce fall risk, especially important if you have joint pain or muscle weakness from your PIDD.

  • Actionable Interaction: Request a referral to a PT, particularly one experienced with chronic conditions or bone health. They can guide you through exercises that won’t exacerbate your PIDD symptoms.

Primary Care Physician: The Holistic View

Your PCP often serves as the hub of your healthcare, managing general health, vaccinations, and connecting you with specialists.

  • Role: They monitor overall health, address general medical concerns, and ensure continuity of care across different specialists. They can also reinforce lifestyle recommendations.

  • Actionable Interaction: Keep your PCP informed about your PIDD and bone health management plan. They can help track progress and ensure all aspects of your health are being addressed.

Conclusion

Boosting bone health when living with Primary Immunodeficiency Diseases is a multifaceted journey requiring diligence, proactive strategies, and close collaboration with your healthcare team. It’s about empowering yourself with knowledge and making informed choices that build resilience from within. By understanding the unique vulnerabilities posed by PIDD, meticulously addressing nutritional needs, engaging in tailored exercise, and leveraging the expertise of a multidisciplinary medical team, you can significantly mitigate the risks of osteopenia and osteoporosis, strengthen your skeletal system, and safeguard your independence.

Every step you take, from choosing calcium-rich foods to incorporating gentle weight-bearing exercises and adhering to your medical plan, contributes to a stronger foundation. This isn’t just about preventing fractures; it’s about enhancing your overall vitality, enabling you to live a fuller, more active life with PIDD. Your bones are your lifelong support system – invest in them wisely.